Brussels keeps its cruising low-key. The best-known outdoor spot is the Bois de la Cambre / Ter Kamerenbos, the big wooded park on the southern edge of the city bordering Ixelles and Uccle, with activity after dark along the quieter paths towards the Drève de Lorraine and the adjoining Forêt de Soignes. It's tolerated rather than official, discreet, and busiest in the evening. It's an unlit public park by day, so use common sense at night: tell someone where you are, keep valuables secure, and stick to paths you can find your way out of.
Indoors, the scene runs through the Saint-Jacques quarter. Stammbar on the Rue du Marché au Charbon is a men's fetish and cruise bar with a darkroom, open most nights. The three central gay saunas — Macho (the largest in Belgium), La Griffe and Oasis — are the reliable year-round option. La Démence weekends at the Fuse club also run a cruisy dark room.