I am planning to book my flight to Athens today and have two options. My previously post it was recommended that we visit the islands first and then the mainland of Greece. With that said it seems to make sense to just fly to the island when we arrive in Athens, is that feasible or is it best for us to spend one night before going to an island. I am not positive of which islands we will visit yet but Santorini is one for sure.Our flight choices are:
Depart Denver 7:40 PM to LHR to arrive in Athens the next day at 7:35 PM (the advantage of this is there is less of a layover in London but we arrive in the evening which makes it probably more difficult to reach an island that evening so would need to stay overnight in Athens for 1 night.
2nd option is:
Depart Denver 7 AM to PHI to Athens 9:10 the next morning. Would we be able to reach one of the islands that day, possibly Santorini?
Thanks for your help.

I think the second option is better as you can fly right to Santorini after you land in Athens at 9am. There are plenty of flights daily from Athens to Santorini, but you may want to search it specifically to see which flight goes well with you. It depends on the season and date (you didn't say your date).

For the first option you'll waste one night in Athens and waste the time for airport -> hotel -> back to airport -> Santorini.

It will probably be May 6th

I also favor the 2nd option . HOwever, If for some reason you must book the first flight, which means you'll be leaving the airport at twilight, (8:30pm) you can take a room near the airport, and catch an early flight out to Santorini in the AM. The Sofitel Hotel (just across from Terminal) is $$$$ but there are several less-pricey options:
• Hotel Peris is plain-jane but well-maintained small place 10 mins away-- offers free shuttle up to 11 pm, also in AM (7:30am on) + continental breakfast. No dinner, but 1/2 mile away is beach w several small tavernas.
• St. Thomas Also 10 min away is small & choice B & B (4 lovely rooms), in olive grove, w. pool. Buffet breakfast (a waste, if u have early AM flight)... w. advance notice can have light evening fare delivered for u.

Certainly arriving early gives you great scope to immediately fly to Santorini.
However even if you arrive Athens at 7:30 pm there is one more flight that evening departing at 21:50 on Aegean. That is sufficient time for you to catch that flight. Prices are pretty good right now on the go lite fare (hand luggage only under 8kilos each) you can get there for 82.36 euros total for both.
If you need to check a bag you can pay for it at booking for an additional 18 euros per bag. Full flex fare including a checked bag is 122 euros for the two of you.
Why waste a night? get out to Santorini without delay.