Gorna Orechovista, Bulgaria
Sofia Observ., Bulgaria
Location: Southeastern Europe, bordering the Black Sea,
between Romania and Turkey
Geographic coordinates: 43 00 N, 25 00 E
Map references: Europe
total: 110,910 sq km
land: 110,550 sq km
water: 360 sq km
Area - comparative: slightly larger than Tennessee
total: 1,808 km
border countries: Greece 494 km, The Former Yugoslav Republic
of Macedonia 148 km, Romania 608 km, Serbia and Montenegro 318 km
(all with Serbia), Turkey 240 km
Coastline: 354 km
contiguous zone: 24 nm
exclusive economic zone: 200 nm
territorial sea: 12 nm
Climate: temperate; cold, damp winters; hot, dry summers
Terrain: mostly mountains with lowlands in north and southeast
lowest point: Black Sea 0 m
highest point: Musala 2,925 m
Natural resources: bauxite, copper, lead, zinc, coal, timber,
arable land: 43%
permanent crops: 2%
permanent pastures: 14%
forests and woodland: 38%
other: 3% (1999 est.)
Irrigated land: 12,370 sq km (1993 est.)
Natural hazards: earthquakes, landslides
Environment - current issues: air pollution from industrial
emissions; rivers polluted from raw sewage, heavy metals, detergents;
deforestation; forest damage from air pollution and resulting acid
rain; soil contamination from heavy metals from metallurgical plants
and industrial wastes
Environment - international agreements:
party to: Air Pollution, Air Pollution-Nitrogen Oxides, Air
Pollution-Sulphur 85, Air Pollution-Volatile Organic Compounds,
Antarctic-Environmental Protocol, Antarctic Treaty, Biodiversity,
Climate Change, Endangered Species, Environmental Modification,
Hazardous Wastes, Law of the Sea, Nuclear Test Ban, Ozone Layer
Protection, Ship Pollution, Wetlands
signed, but not ratified: Air Pollution-Persistent Organic
Pollutants, Air Pollution-Sulphur 94, Climate Change-Kyoto Protocol
Geography - note: strategic location near Turkish Straits;
controls key land routes from Europe to Middle East and Asia
Bulgaria, republic in southeastern Europe, known from 1946 to 1990
as the People's Republic of Bulgaria. Situated in the Balkan Peninsula,
Bulgaria is bounded on the north by Romania, on the east by the
Black Sea, on the south by Turkey and Greece, and on the west by
the Federal Republic of Yugoslavia (Serbia and Montenegro) and the
Former Yugoslav Republic of Macedonia.
Once an independent kingdom, Bulgaria was dominated by the Communist
Party from 1946 until 1990, when a multiparty system was adopted.
During the Communist period, when Bulgaria was under the control
of the Union of Soviet Socialist Republics (USSR), the once-dominant
agricultural sector was overtaken by manufacturing. The capital
and largest city is Sofia.
Most of Bulgaria has a continental climate, with cold winters and
hot summers. The climate in general is more severe than in other
European areas of the same latitudes, and the average annual temperature
range is greater than that of neighboring countries. Severe droughts,
frosts, winds, and hail storms frequently damage crops.
A Mediterranean climate, with dry summers and mild, humid winters,
prevails in the valley of the southwestern Rhodope Mountains; the
northern limit of the climatic zone is the Balkan Mountains.
Background: Having fought on the losing side in both World
Wars, Bulgaria fell within the Soviet sphere of influence and became
a People's Republic in 1946.
Communist domination ended in 1991 with the dissolution of the USSR,
and Bulgaria began the contentious process of moving toward political
democracy and a market economy while combating inflation, unemployment,
corruption, and crime. Today, reforms and democratization keep Bulgaria
on a path toward eventual integration into the EU and NATO.
Size: Approximately 110,550 square kilometers.
Topography: Mostly hills interspersed with plateaus,
with major flatlands in north (Danubian Plateau, extending across
entire country) and center (Thracian Plain). Main mountain ranges
Balkan (extending across center of country from west to east, forming
central watershed of country) and Rhodope (west to east across southern
section of country); include two major ranges, Pirin (far southwest)
and Rila (west central).
Climate: Divided by mountains into continental
(predominant in winter, especially in Danubian Plain) and Mediterranean
(predominant in summer, especially south of Balkan Mountains). Rainfall
also variable, with largest amounts in higher elevations.
Data as of June 1992
The land area of Bulgaria is 110,550 square kilometers, slightly
larger than that of the state of Tennessee. The country is situated
on the west coast of the Black Sea, with Romania to the north, Greece
and Turkey to the south, and Yugoslavia to the west. Considering
its small size, Bulgaria has a great variety of topographical features.
Even within small parts of the country, the land may be divided
into plains, plateaus, hills, mountains, basins, gorges, and deep
Although external historical events often changed Bulgaria's national
boundaries in its first century of existence, natural terrain features
defined most boundaries after 1944, and no significant group of
people suffered serious economic hardship because of border delineation.
Postwar Bulgaria contained a large percentage of the ethnic Bulgarian
people, although numerous migrations into and out of Bulgaria occurred
at various times. None of the country's borders was officially disputed
in 1991, although nationalist Bulgarians continued to claim that
Bulgaria's share of Macedonia--which it shared with both Yugoslavia
and Greece--was less than just because of the ethnic connection
between Macedonians and Bulgarians .
In 1991 Bulgaria had a total border of about 2,264 kilometers.
Rivers accounted for about 680 kilometers and the Black Sea coast
for 400 kilometers; the southern and western borders were mainly
defined by ridges in high terrain. The western and northern boundaries
were shared with Yugoslavia and Romania, respectively, and the Black
Sea coastline constituted the entire eastern border. The Romanian
border followed the Danube River for 464 kilometers from the northwestern
corner of the country to the city of Silistra and then cut to the
east-southeast for 136 kilometers across the northeastern province
of Varna. The Danube, with steep bluffs on the Bulgarian side and
a wide area of swamps and marshes on the Romanian side, was one
of the most effective river boundaries in Europe. The line through
Dobruja was arbitrary and was redrawn several times according to
international treaties . In that process, most inhabitants with
strong national preferences resettled in the country of their choice.
Borders to the south were with Greece and Turkey. The border with
Greece was 491 kilometers long, and the Turkish border was 240 kilometers
Data as of June 1992
The main characteristic of Bulgaria's topography is alternating
bands of high and low terrain that extend east to west across the
country . From north to south, those bands are the Danubian Plateau,
the Balkan Mountains (called Stara Planina, meaning old mountains
in Bulgarian), the central Thracian Plain, and the Rhodope Mountains.
The easternmost sections near the Black Sea are hilly, but they
gradually gain height to the west until the westernmost part of
the country is entirely high ground.
More than two-thirds of the country is plains, plateaus, or hilly
land at an altitude less than 600 meters. Plains (below 200 meters)
make up 31 percent of the land, plateaus and hills (200 to 600 meters)
41 percent, low mountains (600 to 1,000 meters) 10 percent, medium-sized
mountains (1,000 to 1,500 meters) 10 percent, and high mountains
(over 1,500 meters) 3 percent. The average altitude in Bulgaria
is 470 meters.
The Danubian Plateau extends from the Yugoslav border to the Black
Sea. It encompasses the area between the Danube River, which forms
most of the country's northern border, and the Balkan Mountains
to the south. The plateau slopes gently from cliffs along the river,
then it abuts mountains of 750 to 950 meters. The plateau, a fertile
area with undulating hills, is the granary of the country.
The southern edge of the Danubian Plateau blends into the foothills
of the Balkan Mountains, the Bulgarian part of the Carpathian Mountains.
The Carpathians resemble a reversed S as they run eastward
from Czechoslovakia across the northern portion of Romania, swinging
southward to the middle of Romania and then running westward, where
they are known as the Transylvanian Alps. The mountains turn eastward
again at the Iron Gate, a gorge of the Danube River at the Romanian-Yugoslav
border. At that point, they become the Balkan Mountains of Bulgaria.
The Balkan Mountains originate at the Timok Valley in Yugoslavia
and run southward towards the Sofia Basin in west central Bulgaria.
From there they run east to the Black Sea. The Balkans are about
600 kilometers long and 30 to 50 kilometers wide. They retain their
height well into central Bulgaria, where Botev Peak, the highest
point in the Balkan Mountains, rises to about 2,376 meters. The
range then continues at lower altitude to the cliffs of the Black
Sea. Through most of Bulgaria, the Balkans form the watershed from
which rivers drain north to the Danube River or south to the Aegean
Sea. Some smaller rivers in the east drain directly to the Black
Sea. The Sredna Gora (central hills) is a narrow ridge about 160
kilometers long and 1,600 meters high, running east to west parallel
to the Balkans. Just to the south is the Valley of Roses, famous
for rose oil used in perfume and liqueurs.
The southern slopes of the Balkan Mountains and the Sredna Gora
give way to the Thracian Plain. Roughly triangular in shape, the
plain originates at a point east of the mountains near Sofia and
broadens eastward to the Black Sea. It includes the Maritsa River
valley and the lowlands that extend from the river to the Black
Sea. Like the Danubian Plateau, much of the Thracian Plain is somewhat
hilly and not a true plain. Most of its terrain is moderate enough
The Rhodope Mountains occupy the area between the Thracian Plain
and the Greek border to the south. The western Rhodopes consist
of two ranges: the Rila Mountains south of Sofia and the Pirin Mountains
in the southwestern corner of the country. They are the most outstanding
topographic feature of Bulgaria and of the entire Balkan Peninsula.
The Rila range includes Mount Musala, whose 2,975-meter peak is
the highest in any Balkan country. About a dozen other peaks in
the Rilas are over 2,600 meters. The highest peaks are characterized
by sparse bare rocks and remote lakes above the tree line. The lower
peaks, however, are covered with alpine meadows that give the range
an overall impression of green beauty. The Pirin range is characterized
by rocky peaks and stony slopes. Its highest peak is Mount Vikhren,
at 2,915 meters the secondhighest peak in Bulgaria.
The largest basin in Bulgaria is the Sofia Basin. About twentyfour
kilometers wide and ninety-six kilometers long, the basin contains
the capital city and the area immediately surrounding it. The route
through basins and valleys from Belgrade to Istanbul (formerly Constantinople)
via Sofia has been historically important since Roman times, determining
the strategic significance of the Balkan Peninsula. Bulgaria's largest
cities were founded on this route. Paradoxically, although the mountains
made many Bulgarian villages and towns relatively inaccessible,
Bulgaria has always been susceptible to invasion because no natural
obstacle blocked the route through Sofia.
A significant part of Bulgaria's land is prone to earthquakes.
Two especially sensitive areas are the borders of the North Bulgarian
Swell (rounded elevation), the center of which is in the Gorna Oryakhovitsa
area in north-central Bulgaria, and the West Rhodopes Vault, a wide
area extending through the Rila and northern Pirin regions to Plovdiv
in south-central Bulgaria. Especially strong tremors also occur
along diagonal lines running between Skopje in the Republic of Macedonia
and Razgrad in northeast Bulgaria, and from Albania eastward across
the southern third of Bulgaria through Plovdiv. Sixteen major earthquakes
struck Bulgaria between 1900 and 1986, the last two in Strazhitsa
on the SkopjeRazgrad fault line. Together the two quakes damaged
over 16,000 buildings, half of them severely. One village was almost
completely leveled, others badly damaged. Many inhabitants were
still living in temporary housing four years later.
Data as of June 1992
The Balkan Mountains divide Bulgaria into two nearly equal drainage
systems. The larger system drains northward to the Black Sea, mainly
by way of the Danube River. This system includes the entire Danubian
Plateau and a stretch of land running forty-eight to eighty kilometers
inland from the coastline. The second system drains the Thracian
Plain and most of the higher lands of the south and southwest to
the Aegean Sea. Although only the Danube is navigable, many of the
other rivers and streams in Bulgaria have a high potential for the
production of hydroelectric power and are sources of irrigation
Of the Danube's Bulgarian tributaries, all but the Iskur rise in
the Balkan Mountains. The Iskur flows northward to the Danube from
its origin in the Rila Mountains, passing through Sofia's eastern
suburbs and through a Balkan Mountain valley.
The Danube gets slightly more than 4 percent of its total volume
from its Bulgarian tributaries. As it flows along the northern border,
the Danube averages 1.6 to 2.4 kilometers in width. The river's
highest water levels usually occur during June floods; it is frozen
over an average of forty days per year.
Several major rivers flow directly to the Aegean Sea. Most of these
streams fall swiftly from the mountains and have cut deep, scenic
gorges. The Maritsa with its tributaries is by far the largest draining
all of the western Thracian Plain, all of the Sredna Gora, the southern
slopes of the Balkan Mountains, and the northern slopes of the eastern
Rhodopes. After it leaves Bulgaria, the Maritsa forms most of the
Greek-Turkish border. The Struma and the Mesta (which separate the
Pirin Mountains from the main Rhodopes ranges) are the next largest
Bulgarian rivers flowing to the Aegean. The Struma and Mesta reach
the sea through Greece.
Data as of June 1992
Considering its small area, Bulgaria has an unusually variable
and complex climate. The country lies between the strongly contrasting
continental and Mediterranean climatic zones. Bulgarian mountains
and valleys act as barriers or channels for air masses, causing
sharp contrasts in weather over relatively short distances. The
continental zone is slightly larger, because continental air masses
flow easily into the unobstructed Danubian Plain. The continental
influence, stronger during the winter, produces abundant snowfall;
the Mediterranean influence increases during the summer and produces
hot, dry weather. The barrier effect of the Balkan Mountains is
felt throughout the country: on the average, northern Bulgaria is
about one degree cooler and receives about 192 more millimeters
of rain than southern Bulgaria. Because the Black Sea is too small
to be a primary influence over much of the country's weather, it
only affects the immediate area along its coastline.
The Balkan Mountains are the southern boundary of the area in which
continental air masses circulate freely. The Rhodope Mountains mark
the northern limits of domination by Mediterranean weather systems.
The area between, which includes the Thracian Plain, is influenced
by a combination of the two systems, with the continental predominating.
This combination produces a plains climate resembling that of the
Corn Belt in the United States, with long summers and high humidity.
The climate in this region is generally more severe than that of
other parts of Europe in the same latitude. Because it is a transitional
area, average temperatures and precipitation are erratic and may
vary widely from year to year.
Average precipitation in Bulgaria is about 630 millimeters per
year. Dobruja in the northeast, the Black Sea coastal area, and
parts of the Thracian Plain usually receive less than 500 millimeters.
The remainder of the Thracian Plain and the Danubian Plateau get
less than the country average; the Thracian Plain is often subject
to summer droughts. Higher elevations, which receive the most rainfall
in the country, may average over 2,540 millimeters per year.
The many valley basins scattered through the uplands have temperature
inversions resulting in stagnant air. Sofia is located in such a
basin, but its elevation (about 530 meters) tends to moderate summer
temperature and relieve oppressive high humidity. Sofia also is
sheltered from the northern European winds by the mountains that
surround its troughlike basin. Temperatures in Sofia average -2°C
in January and about 21°C in August. The city's rainfall is
near the country average, and the overall climate is pleasant.
The coastal climate is moderated by the Black Sea, but strong winds
and violent local storms are frequent during the winter. Winters
along the Danube River are bitterly cold, while sheltered valleys
opening to the south along the Greek and Turkish borders may be
as mild as areas along the Mediterranean or Aegean coasts.
Data as of June 1992
Like the other European members of the Council for Mutual Economic
), Bulgaria saw unimpeded industrial growth as a vital sign of social
welfare and progress toward the socialist ideal. Because this approach
made environmental issues a taboo subject in socialist Bulgaria,
the degree of damage by postwar industrial policy went unassessed
until the government of Todor Zhivkov (1962-89) was overthrown in
late 1989. The Zhivkov government's commitment to heavy industry
and lack of money to spend on protective measures forced it to conceal
major environmental hazards, especially when relations with other
countries were at stake. Factories that did not meet environmental
standards paid symbolic fines and had no incentive to institute
real environmental protection measures. Even as late as 1990, socialist
officials downplayed the effects on Bulgaria of radiation from the
1986 nuclear power plant accident at Chernobyl'. Citizens were informed
that they need not take iodine tablets or use any other protective
In 1991 Bulgarian environmentalists estimated that 60 percent of
the country's agricultural land was damaged by excessive use of
pesticides and fertilizers and by industrial fallout. In 1991 twothirds
of Bulgarian rivers were polluted, and the Yantra River was classified
as the dirtiest river in Europe. By that time, about two-thirds
of the primary forests had been cut. However, despite its recognition
of the need for greater environmental protection, Bulgaria budgeted
only 10.4 billion leva (for value of the lev-)
to remedy ecological problems in 1991.
Perhaps the most serious environmental problem in Bulgaria was
in the Danube port city of Ruse. From 1981 to 1989, the chemical
pollution that spread from a chlorine and sodium plant across the
Danube in Giurgiu, Romania, was a forbidden subject in Bulgaria
because it posed a threat to good relations between two Warsaw
Pact countries. Chemical plants in Ruse also contributed to
the pollution. Citizen environmentalists opposing the situation
in Ruse organized the first demonstrations and the first independent
political group to oppose the Zhivkov regime . During the Giurgiu
plant's first year of operation, chlorine levels in Ruse almost
doubled, reaching two times the permissible maximum in the summer
of 1990. Over 3,000 families left the city in the 1980s despite
government restrictions aimed at covering up the problem. Besides
chlorine and its byproducts , the plant produced chemical agents
for the rubber industry, and in 1991 some sources reported that
the plant was processing industrial waste from Western countries--both
activities likely to further damage Ruse's environment. International
experts claimed that half of Ruse's pollutants came from Giurgiu,
and the others came from Bulgarian industries. In response to the
formidable Bulgarian environmental movement, some Bulgarian plants
have been closed or have added protective measures; the Giurgiu
plant, however, was planning to expand in 1991.
Pollution of agricultural land from a copper plant near the town
of Srednogorie provoked harsh public criticism. The plant emitted
toxic clouds containing copper, lead, and arsenic. In 1988 it released
toxic wastewater into nearby rivers used to irrigate land in the
Plovdiv-Pazardzhik Plain, which includes some of Bulgaria's best
agricultural land. The groundwater beneath the plain also was poisoned.
Work has begun on a plan to drain toxic wastewater from the plant's
reservoir into the Maritsa River. Environmental improvements for
the copper plant and three other factories in the Plovdiv area (a
lead and zinc factory, a chemical factory, and a uranium factory)
also were planned, but they would take years to implement.
None of Bulgaria's large cities escaped serious environmental pollution.
Statistics showed that 70 to 80 percent of Sofia's air pollution
is caused by emissions from cars, trucks, and buses. Temperature
inversions over the city aggravated the problem. Two other major
polluters, the Kremikovtsi Metallurgy Works and the Bukhovo uranium
mine (both in southwestern Bulgaria), contaminated the region with
lead, sulfur dioxide, hydrogen sulfide, ethanol, and mercury. The
city of Kurdzhali became heavily polluted with lead from its lead
and zinc complex. In 1973 the petroleum and chemical plant near
the Black Sea port of Burgas released large amounts of chlorine
in an incident similar to the one in Srednogorie. Environmentalists
estimated that the area within a thirty-kilometer radius of the
plant was rendered uninhabitable by that release. The air in Burgas
was also heavily polluted with carbon and sulfur dioxide in 1990.
In 1990 environmental scientists claimed that two-thirds of Bulgaria's
population suffered from the polluted environment to some degree
. In 1991 Bulgaria began seeking international assistance in solving
environmental problems. Besides joining Romania, Turkey, and the
Soviet Union in joint scientific studies of the critically polluted
Black Sea, Bulgaria actively sought environmental technology and
expertise from Western Europe and the United States.
Data as of June 1992