A carved slab is situated on the left-hand side of the Caretaker’s Hut [1]. It is a large, white, granite altar with carvings of three steps and a large flat bed on top. There is also a ring pointing in the direction of the solstice; its significance remains unknown.
The Funerary Rock is surrounded by many other foreign rocks such as limestone, which is found in Sacsayhuamán [2] and other quarries far from Machu Picchu. These rocks are believed to have been left over from Inca offerings. Above the rock is a small, four-sided building whose function also remains unknown.
Links:
[1] http://www.moon.com/destinations/peru/machu-picchu/ruins-tour/caretaker-s-hut
[2] http://www.moon.com/destinations/peru/cusco/sights/outside-cusco/sacsayhuaman