subterranean river
river that runs wholly or partly beneath the ground surface
Rattlesnake Creek
subterranean river in the Bronx, New York, United States
Rubicon
underground river in Belgium
River Fleet
subterranean river in London, England
Tyburn Brook
former stream in London, England
Aarhus River
river in Denmark
Hamza River
Aquifer in Brazil in Peru
Earl's Sluice
Lost river in London
Matica (croatian river)
river in Croatia
subterranean waterfall
waterfall inside cavern