De Karperskuyl is a small marina tucked behind the Ottobrug on the Binnenhaven in Hoorn.

To reach it by water, boaters pass through the Binnenhaven and under the Ottobrug, a bridge operated by members of watersportvereniging De Karperskuyl as well as the municipal harbor team.

The harbor is primarily intended for permanent berth holders, so transient visitors have very limited options for mooring here.

Visiting boaters looking for a temporary berth in Hoorn are better served by the Buitenhaven, Binnenhaven, Grashaven, or other local marinas.

Once a year, on the first weekend of September, De Karperskuyl hosts the Hoornse Havenconcerten, a music festival where performers take the stage aboard the charter ship Abel Tasman while audiences watch from small boats or the quayside.