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

Its location on the Vliet makes it easily accessible by boat from multiple directions, as well as by car via the A4 or by bicycle via the blue cycle and footbridge from Voorschoten.

The marina features a modern clubhouse, visitor berths, and a boat ramp where members can launch and retrieve their own vessels.

A tractor-assisted slipway trolley is used for dry winter storage, and the grounds include a workshop, materials storage, an environmental depot for hazardous waste, and covered bicycle parking. The parking area doubles as a dry-storage yard in winter.

The site is secured by an electric gate.