The largest non-subglacial lake in the world is in Dragon 's Breath Cave in Namibia , with an area of almost 2 hectares ( 5 acres ) .
The second largest is in Craighead Caverns in Tennessee , United States .
The largest non-subglacial lake in the world is in Dragon 's Breath Cave in Namibia , with an area of almost 2 hectares ( 5 acres ) , and the second largest is in Craighead Caverns in Tennessee , United States .