Mundeshwari Devi Temple, Bihar
Dedicated to Lord Shiva and his consort Shakti, this temple is considered the oldest functional temple in the world. Believed to have been built in the Saka era, the Archaeological Survey of India (ASI) dates it to 108 AD. The temple has been built in the shape of an octagon – which is a rare style of construction. It is considered to be a specimen of the Nagara architectural style.