This historic bathhouse is now a museum in which wax dummies illustrate the workings of a traditional hammam. Signage is a little garbled ('AD' dates actually refer to Persian Calendar years) but gives an idea of each chamber's purpose. Look for the time stones – translucent, 10cm-thick alabaster panels that glow mysteriously when struck by low sunlight filtering through the skylights, giving bathers a rough idea of the time (at least around sunrise or sunset).
If you don't want to pay to go in, at least admire the quirky, century-old figures painted onto the much older Safavid portal. There's also a display case of antique washing utensils on show in the ticket hall.