authorized equipment for constructing floating bridges and arranging ferry crossings. Engineer troops, road-construction troops, and railroad troops in various armies are supplied with bridge trains. The bridge train includes ferrying and bridge equipment, specially equipped motor vehicles, and vessels, such as towing launches, for transporting equipment through water. A distinction is made between bridge trains that are self-propelled in the water, whose engines are mounted on the ferrying and bridge equipment, and amphibious trains, capable of travel on both land and water, which constitute ferrying and bridge vehicles. There are also special bridge trains for crossing expansive water barriers with strong currents and winds. These special trains are moved by transport aircraft.
With bridge trains it is possible to erect floating bridges over individual floating supports and to construct floating pack bridges of different load capacities. Pontoons are usually used for floating supports and pack bridges. In amphibious bridge trains, floating vehicles are used as supports.
Bridge trains first appeared in the Dutch Army in the early 17th century; the first Russian bridge train, with canvas pontoons, was built in the mid-18th century.