This is a great location right among Hadrian's Gate, Zeus's Temple, the Acropolis Museum, and the southeast gate to the Acropolis. And the Akropoli metro stop is right there too. It is all in walking distance, including many restaurants and shops.
We found the apartment to be large, clean, quiet and comfortable. Since the key box and apartment are a bit far apart (one metro stop), it helps to have a map. We walked from the Keyper to the apartment without difficulty, but it might be a bit more difficult after dark. By the way, the Metro proved to be the best way to get around Athens. It was clean, frequent and safe. Also the best way in from the airport. Only one transfer to get to this apartment.
This proved to be a great base of operations for experiencing Athens' extensive history.