It was renamed "Long Pond" by Europeans, who settled the area in the 18th century for farming and ironmaking, and eventually came to be re-christened "Greenwood Lake."

It was dammed up c. 1765 by Peter Hasenclever of The American Company to increase the size of the lake for water power used downstream at the Long Pond Ironworks.

[2] The original dam was located even with today's Fox Island, with most of the lake extending north of the state line.

The enlarged lake now flooded the Succor Brook at the northern end, forming the East Arm, surrounded "Lime Ridge" to create Chapel Island, and flooded the extreme southern end, including parts of Belcher Creek.

During its resort era, several steamboats operated on the lake, including the Greenwood Lake Transportation Company's Arlington, Milford, and their side-wheeler, Montclair, built in 1876, which had two decks and is reported to have been capable of carrying from 200 to 400 passengers.