St Nikolaus hospital was founded in 1447 by Cardinal Nicholas Cusanus (1401-1464), a humanist and theologian born in Kues. It was built to house thirty-three (Christ's age when he died) old people in need, a tradition still observed to this day. The Gothic cloister and chapel are well worth seeing. Inside, admire the beautiful 15C altarpiece, a bronze copy of the cardinal's tombstone, and the tombstone of Clara Cryftz, the prelate's sister.