Belvidere put-in (Southampton)

The put-in sits on the tidal River Itchen between Northam Bridge just upstream and the river's mouth at Southampton Water downstream. The Itchen is tidal from Southampton Water up to Woodmill, and Southampton's distinctive double high tide gives long periods of slack water at both high and low tide. There is no weir or lock between the put-in and the river mouth.

This stretch is a working part of Southampton's waterfront rather than open countryside: Belvidere Road runs past wharves and a ready-mixed-concrete plant that receives materials by ship, and marinas and boatyards line the river further along, among them Ocean Village, Shamrock Quay, Kemps Quay and Saxon Wharf. Commercial shipping operates on the Itchen up to Princes Wharf, and the tidal river is also the home water of Southampton University Boat Club's rowing crews. Close to the launch, tidal mudflats dry out at low water.

The wider Solent and Southampton Water estuary is a Special Protection Area and Ramsar site, and part of the Lee-on-the-Solent to Itchen Estuary Site of Special Scientific Interest, protecting internationally important numbers of wintering waterfowl and breeding terns and gulls. This is a separate designation from the freshwater River Itchen upstream, which is protected in its own right as a Special Area of Conservation for its chalk-stream habitat.