Hello,
I am debating whether to return the rental car to Athens city center or airport. If I dropped off on a Sunday, is driving in the city manageable. I don't want to waste a 1/2 day and be stuck around the airport if there is another option.
The rental car company reassured me that it's doable.
Yes, it's perfectly doable, especially on a Sunday when traffic is lighter. The rental agency's office in Athens, where you'll return the car, is probably located, like 99% of rental companies, on Siggrou Avenue, a stone's throw from Plaka and the Acropolis Museum.
On this avenue, you'll find gas stations where you can fill up the tank before returning the car.
Siggrou Avenue has a central section dividing the two directions of traffic, which can only be crossed at a few specific intersections as you can see here:
https://maps.app.goo.gl/mRtTwDtwjAWmeVQF6
Depending on the rental agency's location and where you're coming from, your GPS may suggest a slight detour.
Check it out on Google Maps.
Hah, I didn't have a choice with the rental car agency and ended up going up/down the crazy, narrow one-ways in the Plaka to drop off the car. So, if a 60 year old solo traveler can do it, so can you. I'd rather drop off and be in the center than the dreary airport.