Researchers have found a complex of slabs and stones in the Sahara desert that might be the oldest known monument built with astronomical considerations in mind, far older than England's Stoneherge.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/researchers-may-have-found-oldest-monument
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/statesman-new-delhi