Kostnice Sedlec
This is the reason many people outside the Czech Republic have heard of, and make the trip to, Kutná Hora. Forget all that beautiful baroque architecture and descend into the darkness with some bones. The skeletal remains of around 40,000 people have been lovingly arranged in the Kaple Všech svatých (All Saints Chapel), more commonly called the Bone Church. Built in the 16th century, this church forced the movement of a nearby graveyard, so monks from the nearby Sedlec Monastery decided to use the displaced cemetery bones to decorate the church with beautiful, weird, and haunting results. Look out for the chandelier, which is made with every bone in the human body, as well as the Schwarzenberg coat of arms, which includes a raven (assembled from various small bones) pecking the eye of a Turkish warrior.