These train lines -- often only short stretches -- are intended as vocational training systems for kids thinking about a future in the rail industry.
"All of the work on a Children's Railway, from selling tickets to shunting trains, is performed by youngsters. They're usually between the ages of 10 and 14 and the work is usually unpaid. Still, it's not a flagrant violation of child labor laws. Kids actually compete for highly coveted spots running the railroad and they're excused from school for their work.
Begun as "Pioneer Railroads" in the 1930s and expanded in the 1950s, the narrow-gauge railways were a uniquely Soviet and Eastern-bloc phenomenon meant to prepare teenagers for future careers working as railroad engineers, ticket agents and car attendants."