Athens

The capital of Greece and Ancient Greece! And probably the only city you've heard of. Lets go through the major items.

The Acropolis: The crowned jewel of athens, literally sitting on top of a hill. Do yourself a favor and buy tickets from the official website.

https://hhticket.gr/tap_b2c_new/english/tap.exe?PM=P1P&place=000000002

hhticket.gr sells the tickets for all the main historical sites. Don't get ripped off through a reseller.

Go at 8am, its becomes a shitshow very quickly. If you are traveling with elders, tell them to wear grippy shoes and to be VERY careful, I almost slipped on the rocks a few times and I saw multiple people who needed medical attention from falling.

There is a West entrance and a south east entrance. The west is the main one with the ticket booth, honestly I didn't even check if you could get in the south east entrance but you can easily exit from it. Walking around the north of the acropolis along theorias street was really nice, and there is a rock you can climb up (with stairs) with an amazing view of athens while you wait for the site to open. You are allowed to bring water inside, bring your own because the water they sell there is 6 euro.

Knock out the main hill first (perhaps take a quick look at the stadium on the right), and dammit do some reading on the ruins before you go there so you appreciate them. You got the grand entry which is the Propylaea, the Parthenon, and the erechtheion. Don't be like me wondering if I'm looking at the pantheon or the parthenon. Also the greek flag overlooking athens is up there and every tourist is taking a selfie. DONT TOUCH THE MARBLE LIKE THE ASSHOLE TOURISTS.

Then you got the north slope and south slope. Not a lot of people are on the north slope so you can have a gentle walk, and look up at the ancient caves. The connection between the two slopes on the east side was closed, so I had to back track. End your walk by going around the south slope and looking at all the ancient ruins.

If you really wanted to book it, I suppose you could knock it out in an hour. But I read and took my time. Probably spent 2.5 hrs there (thats a lot for me).

The Agora: The original common area for an open and vibrant society! Mostly a bunch of foundations, but if you use your imagination you'll see the birthplace of democracy and the original senate proceedings happening. Also some old sewage ditches! The subway passes by and is covered with cool graffiti.

There are two entrances. One on the north and one on the west. The north one was closed when I was there. 

The Stoa of Attalos was the highlight here, its a two story structure that was restored in the 60 with funds from the Rockefellers. It serves as a museum. I'd start off here and learn the history, then walk around, ending at the Temple of Hephaestus, which is the most complete ancient greek temple!

Pnyx: I was suppose to go here on my first day but after doing the agora and acropolis back to back, I was a sweaty mess and made my way to lunch. Apparently there are some ruins on top and it has an amazing view of the Acropolis. I also imagine you'd get a great view of the port of Piraeus, which I didn't visit because I flew everywhere.