Jachthaven De Vlietopper is the home marina of Watersportvereniging Leidschendam & omstreken, situated in the recreational area Vlietland near Voorschoten and close to both Leiden and Den Haag.

The marina offers more than 300 berths accommodating a wide range of vessel types, from motorboats to sailing yachts, and serves both members and visiting boaters.

Visitors arriving by water should moor at the meldsteiger (check-in pontoon) and contact the harbourmaster by phone. During the sailing season the harbourmaster is on site to assign berths and handle payments.

The marina features modern facilities centred around a clubhouse, making it a convenient and welcoming stop for those cruising the Vlietland waterways.