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.

The Black Sea is more commercially significant to Bulgaria. Burgas and
Varna are thriving ports. Burgas has been a busy port for a longer time,
but Varna has developed rapidly and by 1970 had surpassed Burgas as the
major port and had become the center of maritime industry in the
country. Between 1971 and 1975, for example, the city expects to produce
23,000-ton and 38,000-ton dry cargo ships in series production and to
build one, and possibly more, 80,000-ton tankers.

By 1970 inland waterways--which consisted exclusively of the Danube
River--were carrying only about 0.6 percent of the country's freight
cargo. Because the distances that the average cargo was transported
exceeded those of rail or road transport, however, they accounted for
about 2.5 percent of the total ton mileage. Seaborne shipping carried
about 2.5 percent of the total cargo weight but, because of the far
greater shipping distances, it accounted for nearly two-thirds of the
total ton mileage. Traffic transported by inland waterway remained
relatively constant during the late 1960s and early 1970s; traffic
carried on seagoing vessels was increasing rapidly.

United Nations reports in 1971 credited Bulgaria with the fastest
developing shipbuilding industry in the world. The pronouncement is less
meaningful than it might appear, however, because the industry started
from