The swamps of Sudd in South Sudan are among the largest wetlands in the world. Located in the delta of White Nile, it covers the average area of 30,000 sq. km. During the raining season the wetland can extend to over 130,000 sq. km, which is as much as the size of England. The Sudd is considered almost impenetrable overland or by boat. The abundant water-loving plants form the massive moving blocks. The swamps of Sudd are inhabited by the Dinkas, one the Sudanese ethnic groups.

This is an impassable road that is located between the cities of Syktyvkar, Ukhta, and Pechora in the republic of Komi, Russia. In the beginning of the road, there are only some small pools of water but after a few miles the pools become so large and deep that they are impassable.