The lake Hvalvatn (Icelandic pronunciation: [ˈkʰvalˌvahtn̥] ⓘ) is situated east of Hvalfjörður in the western portion of Iceland.

The surface measures 4.1 km2 (1.6 sq mi), and its greatest depth is 180 m (590 ft).

Not far from Hvalvatn is Glymur, the second highest waterfall in the country.

Hiking trails lead both to the lake and to the waterfall.

This Iceland location article is a stub.