The Dotty Lake Boat Ramp provides water access to Dotty Lake in the Township of Sinclair, within the Lake of Bays area of Muskoka District, Ontario. The ramp is situated at approximately 45. 4482°N, 78. 9773°W.

Dotty Lake itself is a sizeable body of water covering 159 hectares (393 acres), with a maximum depth of 27 metres (89 feet) and a perimeter of 12. 2 kilometres. The lake drains into the Oxtongue River and sits at an elevation of 379 metres.

It is known locally as Long Lake and supports fish species including northern pike, making it a draw for anglers launching from this ramp.