|Location||Province of Rome, Lazio|
|Max. length||2.015 km (1.252 mi)|
|Max. width||1.545 km (0.960 mi)|
|Surface area||2.44 km2 (0.94 sq mi)|
|Max. depth||60 m (200 ft)|
|Shore length1||6 km (3.7 mi)|
|Surface elevation||305 m (1,001 ft)|
1 Shore length is not a well-defined measure.
In ancient times Lake Martignano was part of southern Etruria and called Alsietinus Lacus. Augustus drew from it the Aqua Alsietina; the water was hardly fit to drink, and was mainly intended to supply his naumachia (lake made for a sham naval battle) at Rome, near San Francesco a Ripa, on the right bank of the Tiber, where some traces of the aqueduct were perhaps found in 1720. The course of the aqueduct, which was mainly subterranean, is practically unknown: Frontinus tells us that it received a branch from the lake of Bracciano near Careiae (Galera): and an inscription relating to it was found in this district in 1887.