If you have concerns as a woman traveling alone, we do have a forum for this.
I think you are planning what will be a wonderful trip.
I like the destination choices in your itinerary. I’ve never been to Granada or Seville (in Spain) but have heard good things about both.
Between Greece and Italy: We once ferried overnight from Venice to Corfu, then after visiting the Cycladic islands, we took a plane from Athens to Rome. You have the time to ferry both ways.
(I highly recommend the less touristy areas of Corfu, it is a beautiful island.)

Greece: Athens is good for 2 days, you don’t need any more time there. i spent 4 days in Santorini and loved every second of it. It can be “seen” in a shorter time but given the effort it takes to get there, I think it’s best to stay put on an island for at least 3 days. Rent ATVs to explore the island- very cost cheap and a fun way to get around.

Spain: Madrid and Barcelona are both awesome (and very different). I’d stay 3-4 days in each. From Madrid, Toledo is a great day trip.

Italy: Rome, Cinque Terre, Florence, the Amalfi Coast, & Venice are all must-see’s in Italy for me. If you can’t hit all on this trip, I would be sure to go to Rome (3-4 days), Cinque Terre (3 days), and Florence (3 days, could add a daytrip to Pisa or Siena).

Greece: A lot of people would say stick to the islands, If you go inland check out Meteora
Italy: Florence, Cinque Terre, Amalfi are amazing, if you do enough research, you can spend months in Italy.
You would probably enjoy moving through the south of France on the way to Spain from Italy, this is easy to do, but a cheap flight from Italy to Spain is possible as well. In the south of France: Nice is very nice, Antibes, Sete, Carcasonne, Biarritz. In Spain, I can highly recommend Barcelona, Seville and to an extent Malaga and Ibiza if you enjoy nightlife.

I like taking the ferry between Patras and Bari…it takes a while but is a great experience (guaranteed to see dolphins jumping beside the ship). At night everyone camps on the deck, shares food (make sure to bring some bread, meat, cheese, snacks and water)and passes around a bottle (or two) and has a great time. Recommend the ferry. Get out ogf Bari as quick as possible.

don’t you have anyone to be with on your trip? But I think it is okay to travel alone. You will still enjoy

Italy: I much preferred the coastal towns of positano and sorrento to Rome and Florence
Portugal: Lisbon (and portugal in general) was my favorite place on my entire trip
Spain: barcelona, andalucia, basque country

and i definitely second the advice of get out of bari as quick as possible haha

Thanks for all the advice! What’s the deal with bari? And jhnrbrts unfortunately most of my friends will either still be in school or have boyfriends they don’t want to spend a couple months away from, so I’ll have to do most of it alone. Which I don’t really mind Although my best friend may come for part of the time (yay!)

Not too much in Bari. It’s a big Ferry town, but not the worst port town I’ve ever seen

We spent four days on the Amalfi coast and loved it.
It was a lot cheaper to sleep in Praiano and look at the gorgeous view of Positano than it would have been to stay in Positano itself.
I think there is at least on hostel on the island of Capri, though—at least there used to be.
Capri is worth a visit.
We also spent one night in Sorrento and one night in the town of Amalfi, and the latter town was probably the least touristy of the bunch.

The ferries between Italy and Greece are reasonable, and ferries within Greece are fairly reasonable too.

santorini is heaven on earth if you like old architecture athens is great. also bargain flights you can find from greece to italy, in italy you got tuscany VENICE and ROME which are heavens on earth too, pisa and milan if you love shopping milan is the place for you. u might wanna stop in nice, france before going to barcelona spain also monaco is amazing its were the billionaires and millionaires play there are casinos gambling and it actually can be cheap for backpackers its a great place to stop by for a day or 2 amazing parties

Bari is basically a transportation hub for tourists. In the past it had a reputation as being a bit unsafe (anywhere large numbers of tourists congregate, tends to result in an increase in pick-pockets and scam artisits (ie,. selling fake ferry tickets, etc.)).

There is a old section of Bari that is quite nice, but I found the place to be a bit depressing and unfriendly and overcrowded during the summer.

Metéora is beautiful.

You know…I really hate it when Americans/Canadians who have never stepped foot on the Greek mainland besides Athens (and maybe the port town of Patra), advise other travelers to “stick to the islands”. I understand that Athens (outside of the renovated historic center) was mostly built in the 1960s and afterwards, but it’s really sad that some ignorant people think that Athens (1% of the country) represents that entire mainland. Many of the country’s most gorgeous places are located on the mainland, from Metéora to the Zagoria towns, to the Halkidiki peninsula, and the southern part of the Peloponnese region. And these places are no longer a secret. The southern Peloponnese is gaining a lot of popularity with tourists and retirees from northern Europe, and the Halkidiki peninsula is already rivaling islands (such as Crete, Kos, Rhodes and Corfu) in tourism arrivals. In fact, the places best-known to Americans and Canadians (Mykonos and Santorini) aren’t even the most-visited parts of the country. Crete, Rhodes, Corfu, Kos, Zakynthos, and Halkidiki receive far more tourists than Mykonos or Ios.