Monastiraki is a neighborhood in the historic city center of Athens known for its flea markets, souvenir shops, and some Byzantine churches.
A good place to start is in Monastiraki Square, where you will find action on every corner. The square is full of street performers, street vendors, and more. On the side that borders Ermou, there are a couple large ugly sculptures (one which I used to sit on in with my frappe/souvlaki/tiropita to people watch). There’s also a covered area where you can look down into the ancient sewer system of Athens. Oh yeah, there are also phenomenal views of the Acropolis.
On the square are a few very significant historical monuments. The Pantanassa Church is part of a 10th century monastery that gives the area its name. The Tsisdarakis Mosque (now the Museum of Greek Folk Art) is an Ottoman mosque built in 1759. Next to the mosque is Hadrian’s Library.
Shopping starts just to the west of the square on Ifestou, a pedestrian street famous for its flea market with souvenir shopping and cheap deals. Heading west on Ermou, there are some antique shops. Almost all the streets connected to the square will lead you to a great choice of outdoor cafés and tavernas to pass your time away.
The area also has some impressive churches. A short walk east along Ermou is the Byzantine Kapnikarea church, built in the 11th century. The frescoes covering the entire interior are amazing. If I had to choose one church in Athens to visit, it would be this one. It was definitely my favorite.
Heading east along Mitropoleos takes you to Mitropoleos Square. There you will find Mitropoli, the seat of the Bishop of Athens. It was built in 1862 and was undergoing a significant restoration project when I last visited.
Inside Mitropoli is the tomb of Gregory V, the Ecumenical Patriarch of Constantinople who was hung at the gates of the Patriarchate on the orders of Ottoman Sultan Mahmut II in 1821 in response to the start of the Greek Revolution. His body was dragged around the streets and thrown into the Golden Horn by a Jewish mob, recovered, and later brought to Athens. The relics of St. Filothei are also inside.
Just outside Mitropoli is Panagia Gorgoepikoos, a tiny 13th century Byzantine church with some beautiful masonry work on the outside.