Located in the Sultanahmet district, over the road from Hagia Sophia, this Cistern constructed 527-565AD is unusual. Inside are 336 marble columns and 2 Medusa heads. It is certainly different, you won't need more than about half an hour inside.
Seriously amazing how this water reservoir was built under the city all those thousands of years ago. the precision of the columns and the architecture will leave you mind boggled as to how all this was achieved manually. Remember that if you purchase the Museum card, it does not allow entry into the Basilica Cistern
Tips
Allow no more than an hour for your visit.
Take an extra layer as it is chilly and damp down there.
The queue for entry moves quickly.
A time of writing entry costs 20TL.
https://www.tripadvisor.com/Attraction_Review-g293974-d294555-Reviews-Basilica_Cistern-Istanbul.html
