Help with itinerary / first trip to Greece

I am still contemplating visiting an island.

Hydra IS an island.

Experienced travellers to Greece often suggest that you do Athens at the end of your trip so you can get to the airport easily. I count 14 days in your plan so apparently you will be driving to Athens airport from Delphi on the 15th.

The tourist season does wind down in October but Santorini is likely still open with fewer crowds of tourists.

So if you want to do an Island Santorini is going to be preferable to Hydra.

Here is what I would suggest you do. On arrival in Athens fly immediately to Santorini that day. Athens is a bit wild with hustle and bustle and leaving it to the end of your trip gives you an opportunity to get accustomed to how things work in Greece. Three nights is probably enough time.

Fly back to Athens and rent a car at the airport (assuming you will choose to rent rather than use public transportation)
You have the option of going directly to Nafplio or just drive south and visit the Byzantine city of Mystras and then continue on to Monemvassia. Presumably Monemvassia will still be open for business. Call that 2 nights. Thats 5

Drive to Nafplio In 2 days you can just about fully explore Nafplio proper. The fortress above the city takes half a day alone. Take an additional 2 days for the antiquities nearby. You might be interested in Ancient Nemia. It had sister games to Olympia and the stadium is still there. I suggest that because I am going to suggest you drop Olympia and Kardamelli. Just too far to go.

Thats 9 nights.

Drive north to Delphi. That will likely take up 2 days so thats 11.

Now drive back to Athens for 2 or 3 nights depending on when your return flight is.

Even this plan is ambitious. Greece is best explored slowly.

Here are some images of what I am suggesting.
Nafplio https://www.flickr.com/photos/stanbr54/albums/72157632094108982
Delphi and Meteora https://www.flickr.com/photos/stanbr54/albums/72157698930270992
Peloponnese, Mani and Monemvassia. https://www.flickr.com/photos/stanbr54/albums/72157711323535897

And i did not even mention a visit to Corinth which is close by Nafplio
Corinth Area. https://www.flickr.com/photos/stanbr54/albums/72157711755443483

I made a mistake, I have actually 13 nights. Here is a new draft:
Fly directly to Naxos or Santorini 3 nights
Car to Nafplio 3 nights
Monemvasia and/or Limeni 2 nights
Delphi 1 night
Athens 4 nights with a day trip to Hydra
In this itinerary I’ll skip Olympia and Kardamyli

The other option I am thinking would be as follow:
Fly directly to Santorini 3 nights
Ferry to Naxos 3 nights
Ferry to Athens 4 nights (with a day trip to Delphi)
Car to Nafplio 3 nights

Third option would be to skip the islands all together and focus on the peninsula and the world heritage sites, keeping my initial itinerary. I’d prefer to see less than rushing.

Let me know your thoughts.

I would fly from Naxos to Athens. It's a shorter trip than the ferry. About 40 minutes. Naxos is wonderful but you should research what is open at the end of October. Santorini is always busy so it should be fine that time of year. I highly recommend renting a car for a day to explore Santorini. The caldera views are stunning but there is more to Santorini than just the caldera views. If you do visit Naxos, I highly recommend renting a car for a day there as well to explore this beautiful and interesting island

If you decide to omit the islands, I would spend 4 or 5 nights in Nafplio. Mystras, the Byzantine ruins, is my favorite, and worth the drive from Nafplio, about 1 hour and 45 minutes.

For option 'one' I would not bother with Hydra if you have gone to some other island.

For option 'two', I would do Athens at the end to simplify departure

You provided your preferred options. I would choose your first new plan.
Here is a new draft:
Fly directly to Naxos or Santorini 3 nights
Car to Nafplio 3 nights
Monemvasia and/or Limeni 2 nights
Delphi 1 night
Athens 4 nights with a day trip to Hydra

My thoughts: Santorini will be active in late October. Naxos has a permanent population so Naxos town will still be up and running but much as I love Naxos tourist season is basically over. I think Santorini is the best option because tourist infrastructure is still operating. Santorini really is a must see.
Santorini also has more flights daily so more options for connections in Athens.

Do fly back to Athens from Santorini. Pick up a car at the airport. Check ACR they are the most recommended car rental company on these forums.
I would drop that day trip to Hydra and add that day to the Monemvassia, Limeni Delphi portion of the trip.
3 nights Athens.

Thanks to all for your feedback. I actually decided to focus on the Peloponnese peninsula (and the world heritage sites) for the whole trip adding more nights in Nafplio and on the Mani peninsula instead of Kardamyli. I’ll keep Olympia as well. I’ll leave the Cyclades for another trip.

I hope you aren't still stuck on Hydra as your only island visiti ... what is the attraction for you? A movie you saw, or the incessant promotion by R Steves? It has a lovely harbor, but beaches almost non-existent, no archeological interests at all... celebrities have homes there, hidden away. I If you want a day-trip island from Athens, I highly recommend Aegina... only 1 hr on ferry... and if you take a conventional ferry with open back deck (NOT a closed-cabin hydrofoil) you get a "mini-cruise" enjoying the seascape -- huge cruise ships, freighters, 3-masted schooners, tiny sailboats. (I think Hydra is only accessible via hydrofoils).

The island has a FAB temple on hilltop mid-island, w 360° view of Saronic Gulf... and a port town with back streets full of shops, quite greek. It's not a pretty-pretty "postcard look" but not fake either -- most visitors are Athenians on a quick getaway. TO get around, there is local bus service, taxis and also motor-assisted e-bikes. It's easy to get to the port of Pireaus for your ferry -- the Green Line Metro takes 30 minutes from Monastiraaki station. And if you time it right, the ferry going back to Piraeus can be a sunset treat. Here's an interesting photo album of such a daytrip - http://www.flickr.com/photos/36264706@N03/sets/72157621604646139/detail/

Great. I’ll look into Aegina. As for Hydra, I already removed it from my plans for more days in Nafplio and the Mani peninsula. Yes this was Steve’s itinerary.

I would not plan my itineraries based on Rick's itineraries. The destinations, yes, but not the number of nights in each place. His trips move around too much, and you are hardly in one place for any length of time to really appreciate a place and see all the important sites. He typically has only one and two-night stays, and occasionally a 3-night stay. I know this sounds corny, but stop and smell the roses.

I was on Hydra many, many years ago, and I agree with Janet.

Miammiam, Focusing on the Peloponnese makes sense especially given the time of year. Focus on the islands for another trip.

I have re-worked my itinerary as follow:
Day 1: arrival in Athens - 3 nights in Athens
Day 2: visit of Athens
Day3: visit of Athens
Day 4 rent a car and road to Nafplio with stop to visit Ancient Corinth and Mycenae Archeological site. 3 Nights in Nafplio
Day 4 visit Nafplio and Tiryns
Day 5 visit Epidavros site and village.
Day 6 drive to Mystra visit site - 1 night in Mystra
Day 7 drive to Monemvasia visit Castle of Gerald on the way - 1 night in Monemvasia
Day 8 drive to Mani visit Areopoli and stay in Limeni - 2 nights in Limeni
Day 9 visit the Mani area
Day 10 drive to Olympia with stop at Bassae temple - 1 night in Olympia
Day 11 visit Ancient Olympia site and drive to Galaxidi - 2 nights in Galaxidi
Day 12 visit Delphi site
Day 13 drive to Athens stop at Hosios Loukas Monastery - 1 night in Athens
Day 14 departure.

From day 10 it’s more driving than I would like but I don’t see how to do otherwise if I want to include Delphi. I also wanted to add the lousios Gorge on my itinerary but it seems too much out of the way. I thought of passing on Olympia to go to Lousios instead and then Delphi bit it’s more driving.
Initially I was going to drive from Nafplio to Monemvasia stopping to visit Mystra but I thought it would be too much in one day. So I removed one night in Monemvasia for Mystra to have more time there.
Anyway please let me know your thoughts and if you have any suggestions. Thank you.

We did the Rick Steves Greece tour in 2019. My favorite stop was Monemvasia. Kardamyli was lovely, but um, more on the relaxing side. Not a lot of site attractions. Loved Hydra too, but that is the only island we went to. Greece is wonderful, you will love it!