Behind the gilded 18th-century Carmelite Church of Nossa Senhora do Carmo lies one of Portugal's strangest sights. The Chapel of Bones is a small room — barely six metres by three — whose walls and ceiling are completely covered in human bones and skulls arranged in geometric patterns, with two complete skeletons hanging on the walls.
Entry is from inside the church and costs a couple of euros. The Carmo church itself is worth a look on the way in for its lavishly carved Baroque altars and gilded wood. It is open Monday to Friday and Saturday morning; closed Sundays. Quieter and more haunting than the larger ossuary at Évora.