Figure 4. Communications Systems of Bulgaria, 1973

Table 2. Use of Transportation Facilities in Bulgaria, 1960 and 1970

Total Freight¹Ton Miles²
Cargo Traffic:1960197019601970
Railroads 38.4 68.2 4,360 8,650
Motor transport128.3 492.8 1,270 4,940
Seaborne shipping 1.1 14.5 1,530 24,375
Inland waterways 1.6 3.7 384 1,145
Air transport 0.007 0.083 0.2 9
Total Passengers²Passenger Miles²
Passenger Traffic:1960197019601970
Railroads 79.0 106.1 2,260 3,890
Motor transport 72.6 282.0³ 1,020 3,740³
Seaborne shipping 0.6 0.6 12 17
Inland waterways 0.8 0.3 29 19
Air transport 0.2 1.1 56 750
¹ In million tons.
² In millions.
³ 1969 information.
Source: Adapted from Statistical Yearbook, 1971, Sofia, 1971.

Conversion from steam to diesel and electric locomotives is proceeding rapidly. As late as 1962 the country had no diesel locomotives and only a few passenger-carrying electric trains. By 1972, about 80 percent of the freight and a larger proportion of passenger traffic were carried on diesel or electric trains. Steam locomotives will probably have been replaced completely by 1978.

Roads

Construction is expensive, engineering problems are frequently challenging, and the roads are difficult to maintain on the mountainous terrain, with its many narrow and steep gorges. Ice and snow close most routes at times during the winter months. Spring thaws and floods damage the best roads and make the poorer roads impassable for considerable periods. Of the approximately 21,000 miles of roadway, about 8,000 are paved, another 8,000 have surfaces hardened with stone or gravel, but nearly 5,000 remain dirt surfaced.

Waterways

The 290 miles of the Danube River that flow along the northern border are navigable. Other streams are too short, too shallow, or have too great gradients to use or to allow development as waterways. The fact that the Danube leaves the country to exit into the Black Sea from Romania limits its potential as an avenue to seagoing trade, and the fact that it flows along the country's periphery keeps it from being the central feature that it is, for example, in Hungary. Bulgaria's entire portion of the river is, however, downstream from the Iron Gate and thus can handle 2,500-ton vessels. There are no locks or dams in this area and, although it freezes for a short time in the winter and floods during the spring, it is usable for an average of about 300 days per year.