Dublin Airport to To Belfast??

If your return flight is from Dublin, then yes, that is what I would do. My nephew and friends were supposed to go this month and that is what we had worked out together. The first day is usually a wash anyway so you might as well use it to do your train traveling. You will definitely get some sleep on the train to Belfast to help get over some jet lag. Then you can check into your hotel, walk around, have an early dinner, go to sleep early and hopefully wake up the next day well rested.

You'll have a better chance of getting into a hotel earlier if you contact the hotel directly and ask to be assigned a room that is ready vs just showing up and hoping. We did that once in Amsterdam and the hotel initially said there would be a charge to guarantee the room would be ready. We opted not to but upon arrival mid morning were given a room right away.

Worst case the hotel should offer to store your luggage, give you a time when your room will be ready then you can go sightseeing. Just be ready with your gear sorted so you know what you want with you and the rest locked up - daypack, passport, cash/cards, water bottle, jacket, etc.

Not a bad idea to head to Belfast first given your very early arrival hour.

Thank you to you both! Planning a trip is always fun, but especially now - when we need to think of the future...

There is another way to assure early check in, pay for the night before and let the hotel know you will be arriving in the am. Your room is guaranteed ready and you can pop right into that shower! I did this once after a red eye flight from Rwanda to Amsterdam. Nine hour overnight flight in the same time zone. Worth every penny! The hotel treated me very well. They respected that I did this. I arrived, took a shower, took a two hour nap and then set off to explore the city refreshed. I passed a crowded waiting area in the lobby of exhausted travelers and their luggage hopefully waiting for a room to open up.

I like the Premier Inn Titanic Quarter as my Belfast hotel. Great prices, great location On river near Titanic Experience. No charm, but it is more likely you’ll be out finding the charm in the city itself. It is a very nice walk to downtown along the river or catch the public bus in front of the hotel.

The drawback of the train is that is requires you to first get to central Dublin from the airport. Personally i'd take the direct bus from the airport to Belfast. https://www.aircoach.ie

Paying for the previous night would definitely do the job, but may cost more than just the fee for early checkin. The hotel in Amsterdam that I mentioned would have only charged about a quarter of one nights lodging for early check in. I'd ask for early check in hoping it would be free, then if they mention a charge see if that's less than 1 nights stay.

You said you were taking the bus, not the train, correct? Are you thinking of the Aircoach buses? They’re really nice.

I would vote for the bus from the airport to Belfast too. Are you going back to see Dublin? If so, the train goes from Belfast to Dublin several times a day, as does the bus.

Everyone has been so helpful I thought to share our evolving plan. We are interested in the history, less so nature/natural wonders (our knees can't hike any more). Suggestions or comments?

Take the hourly Aircoach bus from Dublin Airport to Belfast (2 hours) and then get a taxi to a hotel (we'rev looking at the Europa and Fitzwilliam but no decision yet. We love Premier Inns but thought we'd splurge a bit). The prices in Belfast are so much less than in Dublin, we may make reservations for the night before to be certain that we can get in and take a shower before heading out.

Day 1 - Belfast Arrive, taxi tour w/Peace Walls and Titanic Quarter.

Would you recommend Irish, Black or Cab Tours? Ww would love a good, historical tour.

Day 2. Belfast Walking tour, Crumloin Rd Gaol, St Malachys church, pub dinner at Crown Liquor Salloon.
Would you recommend -- Coiste Irish Political Tours and/or Sandy Row Walking Tours or About DC Tours A History of Terror

Day 3 Train or bus to Derry. Which would you recommend?
Martin McCrossan walking tour of the city, Tower Museum

Day 4. Derry Bogside history tours, Museum of Free Derry Museum, Tower Museum, Derry-Coleraine Railway

Day 5 Train to Dublin

Thank you!!

Many thanks - hugely helpful!!!

Take the hourly Aircoach bus from Dublin Airport to Belfast (2 hours)
and then get a taxi to a hotel (we'rev looking at the Europa and
Fitzwilliam but no decision yet.

I would not bother with a taxi to the hotel. The bus will drop you off around 100 m from Europa and 150 m from Fitzwilliam.

I didn't know!! Thank you!!

Several comments lead me to think that Derry would not warrant 2 days. Is this true???