Ireland or Ireland and London

I'd focus on visiting London and then skipping Dublin and going to western Ireland. It would be unfortunate to skip Dublin -- I have been to the Irish capital four times; it feels like a second home to me -- but the museums in London are spectacular. This is important given that you underline museums.

No, I don't believe 11 days of just sightseeing is too short. However, I always wish I could have stayed longer in each of the 17 international trips I have made. You might feel the same.

You mention the love of hiking and the wish to visit Dingle. One idea to save time is to hike part of the Dingle Way (https://www.dingleway.com/), rather than Killarney National Park. I hiked all 100 miles of the Dingle Way over seven days in 2010. You could walk just a 15-mile section or two of it. Also, you say your kids love ruins. Dingle has more ruins -- Celtic, Christian, Norman, other -- than you can shake a shillelagh at.

Maybe cut Newgrange from your list to save time. It and the Hill of Knowth -- I've seen both of them -- are fascinating sites, but they're in eastern Ireland. You'd have to drive there all the way from the west. An alternative idea is the see the Rock of Cashel (https://heritageireland.ie/places-to-visit/rock-of-cashel/), a knockout site guaranteed to entrance any romantic adult or kid at heart. That will also involve a bit of a drive from the West, but it wouldn't be as far as Newgrange.

Want an idea from way out there? Once I took an overnight ferry from Cork, Ireland, to the Swansea, Wales. If you want to give you kids and yourself a memorable experience, book a ferry to cross from England to Ireland. It'll consume a bit of time, but why not? The Cork-Swansea ferry might have been discontinued, but there are others. There used to be Portsmouth to Ireland ferry, but I'm not sure about that one either. The Hollyhead, Wales-Dublin ferry is popular. You'd have to do some investigating of ferry offerings.

With your allowance of days, make London your city time (at the end), and skip Dublin. Fly in to Shannon, see the places on the west side of Ireland (are you renting a car, or using bus/train?), then make your way towards your Newgrange destination. For a base prior to visiting Newgrange, and for a place to stay before your flight from the Dublin airport to London, consider Trim. It’s a small city with its own castle, about an hour’s drive from the Dublin airport the day you’re ready to move on to London.

Ryanair also fly to Shannon from London Stansted and London Gatwick and Aer Lingus fly there from London Heathrow

I agree with CL: You can't go wrong with more time in London. There are so many things that are free. You can get a family pass with www.nationaltrust.org.uk to see many more sites in Metropolitan London. The pass also works in Northern Ireland. They would love the street markets. Highgate Cemetery and others are spooky fun. Hampton Court Palace has costumed guides that make history come alive. Windsor Castle has a real King. Many of the great Museums are free. Boat rides on the Thames. Visiting Greenwich with the Guide Meridian at the Observatory. Etc. Wait 10 years to take the kids to Ireland, that way everyone can enjoy a Pint.

My wife and I went to Ireland one May--flying into and out of Dublin. Most of our time was spent in a rental car in the southwest driving around the coastline. The area has some fine B&B's--which is where we stayed.

May is a little before the tourists come, and we found the Irish countryside to be somewhat boring. And out of all the major cities of Europe (which is a lot), Dublin was about our least favorite city. Ireland is just not our "cup of tea."

For a first short trip to Europe, my favorite itinerary would be London and Paris. Or if time allowed, London, Paris and Amsterdam. They're just all such important cities--and must sees.

I'm going to say the opposite - if you are not city people, then skip London and just concentrate on Ireland. 11 days isn't a lot of time and you will easily fill your time in Ireland. Newgrange is best done from Dublin and was the highlight of our trip. Allow plenty of time so you can visit Knowth as well as Newgrange. They are completely different and we enjoyed both. Tie it in with a visit to Hill of Tara and Trim Castle.

From Dublin head to Killarney, having a stop in either Rock of Cashel or Cahir for the castle. There is Ring of Kerry, Kerry Cliffs (even more impressive than Moher?) Go for a ride up the Gap of Dungloe in a jaunting car. Go and find the tradtional farms in Muckross house let the kids talk to the costumed interpreters about life 100 years ago...Visit Ross Castle. Do the Ring of Beara and go for a ride on the cable car across to Dursey Island. Go and find the 'Hag of Beara'' and learn about its folk lore

Dingle peninsula can be done from Killarney to save relocating.

Then head up to say Doolin with a stop at Bunratty Folk Museum on the way (great fun for kids of all ages...) Do the Cliffs of Moher - best seen from the bottom on a boat tour. Think about a day trip to one of the Arran islands. Explore the limestone scenery of the Burren and Poulnabrone dolmen.

Either fly out of Shannon or return to Dublin via Athenry with its ruined castle and town walls and also Clonmacnoise early Christian site with its round towers, ruined churches and lovely carved crosses.

That has probably filled your 11 days and theres lots more I've not mentioned...

I think wasleys idea is the best given the time you have. London is a huge city with many major sights, and I think giving it just three days is going to feel extremely rushed. Then the time you spend getting from there to Ireland will just eat into the rest of the time you have and you will be rushed so squeeze in what you want to see there. I would suggest flying into Dublin and doing a guided day trip to Newgrange, and maybe some sights in the city such as Killmainham Jail, then rent the car and drive towards Killarney, stopping at a couple sights along the way. The park is wonderful, you can take a boat ride across the lake, a jaunting car ride through the Gap of Dunloe, or even rent bikes. You can then drive up the west coast to cliffs of Moher and Burren and spend some time in Galway from which you might also take a trip to the Aran islands, or drive the Connemara area. All of this is a lot, even with a full eleven days on the ground. Starting in Dublin means you will have some time to get used to the time change before getting the car. You want to avoid backtracking too much in order to maximize your sightseeing time, but given what you want to see you may have to do some, if you can fly into Dublin and out of Shannon that will help. Leave London for another trip.

Thank you everyone for the great feedback.
This helped solidify my feeling that we should pick either Ireland or London. I love the suggestions for itineraries without Dublin and the idea of adding a day trip to the Aran Islands.
Selfishly I'd like to go somewhere I haven't been, but realistically focusing on London may be better for the ages of our children. It removes hotel changes and driving from the equation.

We recently took our kids (11 and 7) to London and Paris. I'd also been to both several times, but I felt they were the best option for their ages. They loved London. We did daytrips to Hampton Court Palace (it wasn't busy at all) and Warner Bros Studio Tour. If you're kids like Harry Potter, I highly recommend that tour, it was my daughter's favorite part of the trip. I'd probably focus on either London/England or Ireland. We ended up spending 8 nights in London and were able to fill every day and didn't do everything we wanted to.