De Duikelaar is a watersports centre and marina situated on the northern shore of the Sloterplas in Amsterdam's Nieuw-West district.

It serves as a welcoming base for both beginners and experienced water sports enthusiasts, offering sailing lessons, canoeing, stand-up paddleboarding, windsurfing, and equipment rental.

Courses are available for children, adults, and groups including schools and companies. The marina accommodates up to 120 vessels, with berths suitable for boats up to twelve metres in length and a draught of 1. 5 metres.

By water, the Sloterplas is reached via the Akersluis (lock no. 102) or the Cramergrachtsluis (lock no. 112), both remotely operated. Vessels with an air draught of 2.

10 metres can generally pass under the bridges, though checking current water levels is advised.