The lake is surrounded by beech forest and is 82 metres (269 ft) deep.

The New Zealand Ministry for Culture and Heritage gives the Māori translation of Rotoiti as "little lake".

Thomas Brunner and Charles Heaphy reached the lake in November 1843, and Heaphy named it Lake Arthur after Captain Arthur Wakefield, but the Māori name remained.

Kerr (who introduced Trout to the lake),drowned there with many believing his son Robert to be responsible.

Rotoiti is also a popular place for waterskiing and is adjacent to Mt Robert, which hosted a small club-owned skifield, until it was removed by DOC in 2005.