Just one block downhill from Museo de Arte Precolombio [1] along Palacio, the Museo de Arte Religioso (Palacio and Hatun Rumiyoc, 8 a.m.–6 p.m. daily, US$5 or boleto religioso) resides in a colonial building that was built by the Marquis of Buenavista and later occupied by Cusco’s archbishop. These days its handsome salons showcase religious paintings from the 17th and 18th centuries.
Walk up the alleyway Hatun Rumiyoc and you will see that the entire museum is built upon a foundation of Inca stones that fit perfectly into one another. This was the foundation of an early ruler of Cusco [2], Inca Roca, and near the end of the street you will find the famous stone with 12 sides, all of which conforms perfectly to their neighbors.
Sadly, the stone was badly chipped and scarred by a group of unknown vandals in April 2004.
Links:
[1] http://www.moon.com/destinations/peru/cusco/sights/northeast-the-plaza-de-armas/museo-de-arte-precolombino
[2] http://www.moon.com/destinations/peru/cusco