The design of the Metrotram seen in Kryvyi Rih has its roots in the socialist urban planning guidelines that were formulated in the 1960s, based on models of the emergence of new urban centers and the transport arrangements that would suit them, in particular, how a small settlement would grow into a full-sized city, and at which point a rapid transit system would need to be built. Kryvyi Rih and Volgograd were both chosen to test whether construction of a full-scale metro system could be avoided by adopting a light rail design for a socialist city. Both cities had developed tram networks, but like most urban centers, overcrowding and widespread congestion proved too much for the trams to serve as the main transport arteries. Moreover, both cities were destroyed in World War II and rebuilt, with all the requirements of a modern city considered in planning.