The imposing castle dominates the image of Blankenheim. Finds indicate that a Roman fort previously stood here. Gerhard I built the castle in 1115 above the source of the Ahr. Today the castle complex serves as a youth hostel and can be visited on request. Blankenheim Castle is located directly on the hiking trails Burgen-Route and Eifelsteig stage 6.
The 566-meter-high, erosion-shaped volcanic cone is home to the impressive millstone caves, where angular lava clinker and porous rock provide an impressive insight into the volcanic past of the region.
The Kreuzwäldchen is a peaceful and completely idyllic area. South-west of the village of Kempenich, on a small hill, stands the chapel of the "Our Lady of Sorrows", which was built in 1879 by the pastor Ferdinand von Freyhold.