Interlachen is a town in Putnam County, Florida, United States. The population was 1,475 at the 2000 census. The town is part of the Palatka Micropolitan Statistical Area.
Interlachen is located at 29°37′22″N 81°53′41″W / 29.62278°N 81.89472°W / 29.62278; -81.89472 (29.622709, -81.894680).
According to the United States Census Bureau, the town has a total area of 6.4 square miles (16.7 km²). 5.8 square miles (15.0 km²) of it is land and 0.6 square miles (1.7 km²) of it (10.08%) is water.