Hiidenvesi (Finnish pronunciation: [ˈhiːdenˌʋesi]; lit.

'hiisi water') is the second largest lake in the Uusimaa region in Finland.

The biggest part of the lake is located in the municipality of Vihti and smaller parts in the town of Lohja.

Both lakes are part of the Karjaanjoki (Swedish: Svartån) basin that drains into the Gulf of Finland.

This Southern Finland location article is a stub.