Othership Flatiron is a guided sauna and ice bath studio on West 20th Street, steps from Madison Square Park. Facilitators lead each session through heat, cold and breathwork: a Western Red Cedar performance sauna heats to 185°F with aromatic snowballs, and eight ice baths, including custom four-person tubs, are kept between 32 and 40°F. Drop-in sessions and multi-session packs are sold, with an intro two-week pass at $135, and the space also hosts private events.