The railroads also continue to give way to motor vehicles in numbers of passengers carried. Between 1960 and 1970 the situation changed radically; on the earlier date the railroads carried more passengers than buses did, but a decade later they carried hardly more than one-third as many. In long-distance passenger travel, the railroads remained the major carrier by a narrow margin in 1970, although the difference was narrowing. [Illustration: _Figure 4. Communications Systems of Bulgaria, 1973_] _Table 2. Use of Transportation Facilities in Bulgaria, 1960 and 1970_ -------------------+-------------------------+------------------------- | Total Freight* | Ton Miles** Cargo Traffic: |------------+------------|------------+------------ | 1960 | 1970 | 1960 | 1970 -------------------+------------+------------+------------+------------ Railroads | 38.4 | 68.2 | 4,360 | 8,650 Motor transport | 128.3 | 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 Passengers** | Passenger Miles** Passenger Traffic: |-------------------------+------------+------------ | 1960 | 1970 | 1960 | 1970 -------------------+------------+------------+------------+------------ Railroads | 79.0 | 106.1 | 2,260 | 3,890 Motor transport | 72.6 | 282.0+ | 1,020 | 3,740+ Seaborne shipping | 0.6 | 0.6 | 12 | 17 Inland waterways | 0.8 | 0.3 | 29 | 19 Air transport | 0.2 | 1.1 | 56 | 750 -------------------+------------+------------+------------+------------ * In million tons. ** In millions. + 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