Strabo Geography 16.2.44

[44] Many other proofs are produced to show that this country is full of fire. Near Moasada ¹ are to be seen rugged rocks, bearing the marks of fire; fissures in many places; a soil like ashes; pitch falling in drops from the rocks; rivers boiling up, and emitting a fetid odour to a great distance; dwellings in every direction overthrown; whence we are inclined to believe the common tradition of the natives, that thirteen cities ² once existed there, the capital of which was Sodom, but that a circuit of about 60 stadia around it escaped uninjured; shocks of earthquakes, however, eruptions of flames and hot springs, containing asphaltus and sulphur, caused the lake to burst its bounds, and the rocks took fire; some of the cities were swallowed up, others were abandoned by such of the inhabitants as were able to make their escape.

But Eratosthenes asserts, on the contrary, that the country was once a lake, and that the greater part of it was uncovered by the water discharging itself through a breach, as was the case in Thessaly. ³