Leidseplein, as it sleeps
The key to a good slow session near the square is the room. Hotels on the Leidseplein itself and on the Leidsestraat sit right in the thick of things, and a room facing the street will hear music and conversation until very late. The canal-house hotels along the Leidsekade, looking over the water of the Singelgracht, are much calmer, and the larger modern hotels toward the Marnixstraat usually have better glazing. If you are booking the hotel as well as the session, ask for a high floor at the back. Once inside, shut the windows, which cuts most of the noise, and lower the lights to a single lamp. Silence the notifications on your phone too, because a slow session is easily broken by a buzz on the nightstand. For couples, check that the bed is wide enough for two people to lie side by side, since two women working together need that much space.