One feature commonly found along the Inca Road are shrines. Shrines along the road vary a great deal--some are merely piled rock; others are elaborately carved and shaped boulders; and some are the mountains themselves.
Christie (2008) identified four types of carved rock shrines found along the Inca road. The first type is carved or fore-grounded rocks as primary trail/road markers, such the major carved rock complex at Kusilluchayoq on the outskirts of Cusco. The second type is carved or fore-grounded rocks at places with significant views, such as the seat-like carving at Machu Picchu illustrated in the photo above.
Christie's third type of shrine is carved or fore-grounded rocks as delimiters of important sites, such as the complex near the estate of Topa Inca [AD 1471-1493] at Chinchero. And the fourth type is that marking the route of ceques, pilgrimage roads of the Incas that were not built, but rather marked by a series of wayposts.
Sources and Further Information
Christie, Jessica J. 2008 Inka Roads, Lines, and Rock Shrines: A Discussion of the Contexts of Trail Markers. Journal of Anthropological Research 64(1):41-66.
Hyslop, John. 1984. The Inka Road System. Academic Press: New York.
McEwan, Gordon F. 2006 The Incas: New Perspectives. Santa Barbara: ABC-CLIO.