Is this crazy? Fly to Dublin to get to London?

You would go through customs and immigration in Dublin. In London you would arrive in the same manner as a domestic passenger - no further passport checks is routine. Flying back to Dublin you will have to go through a passport check whether connecting directly or leaving the airport. I have had no problems with Aer Lingus, haven't touched Ryanair. The Aer Lingus Irish breakfast is worth the money (presuming you are likely to arrive overnight). British Airways is also an option. If your Dublin->London flight is separate, take care to leave enough time between them though, depending on how risk-adverse you are.

Have your priced flying Aer Lingus from Denver to London (through Dublin) all on one ticket? This way, if you miss your connection, Aer Lingus will put you on the next flight at no charge. If you are on separate tickets and miss your connection for any reason, YOU are responsible for new tickets at last minute prices (potentially thousands of dollars on the Dublin to Denver leg). As always when the subject of Ryanair comes up, I must post a musical warning about the perils of Cheap Flights (not safe for work - contains profanity): http://tinyurl.com/2vxmaod "There must be extra charges when the flights are 50p"

hi, the only experience i have is with Aer Lingus so far. It was a puddle jumper from Dubln to Edinburgh. They charge you to choose a seat and you cant check out with out (w/o) doing so. also, on my short flight, whey wouldnt allow your to hop seats once you were in flight. They said the plain was "balance for everyone and cargo. I dont know about any of the transatlantic flights but read the fine print. i try to leave at least 2 hours between flights, but on my last trip i got screwed anyway. you may want to readup on whats there to do/see in dublin. i really dont know what floats your boat. if you like to Party, they love to start on Thrusday PM. if you like history, the book of Kells is cool along with the Trinity Library. again, dont know what your likes are but i enjoyed them. as far as lodging i stayed at the Harding Hotel. Its about 3 blocks away from the Temple Bar area, 2 blocks from the river and next to Christ Church. happy trails.

EDIT: I reread your question, and see that you plan to spend some time in Dublin on your return. So, my dire warnings about last minute tickets from Dublin to Denver don't apply. In that case, your plan can work, as long as you are aware of all of Ryanair's tricks, and have allowed lots of extra time for the connection on the way in.

We flew Ryan Air from Liverpool to Dublin because they were the only carrier flying into Dublin from there. Flying Ryan Air is more like being trapped in an agressive timeshare upsell presentation than flying an airline. Everything - and I mean everything you might want on a flight is extra. The seats don't even have pockets on the back them and are instead just plastic with the emergency instruction cards printed on them. In addition they will use any excuse of not following the rules and jumping through hoops to charge you more money. Didn't print out your boarding pass at home? Charge. Your carry on is thicker than our crazy thin guidelines so you have to check at the gate? BIG charge. In Liverpool there was a vending machine with cheapie backpacks in it you could buy to try and split up your stuff or make a carry-on after they insisted you check your bags and charged you for it. We were fine and things went exactly as planned and flew for the price we paid on-line but consider it carefully and read all the rules. It was fine for puddle-jumper flight but I can't imagine flying them for any serious travel time. Flying into London you should have other choices - I've flown BMI but they have been swallowed by BA and may not exist as a separate choice anymore. Good luck,
=Tod

Kathy, make sure that you check flying into Dublin, and back from London, or just the opposite. That is "somewhat" what we did to get a good price on our flights this May/June. Actually we found the best price flying into London, and out of Shannon. To check these options use the "multi-city" option in your airline search. Use Skyscanner.com to search for lo-cost flights between England and Ireland. We found a great deal on flights on City Jet, an Air France subsidiary. We have used Ryan Air, and think that any other lo-cost option would be a better choice.

Kathy, I've flown lots of times with Ryanair. The debate about that airline will never end, I think!
You have to read, and follow, the instructions. If you do that, you'll be fine. They NEVER break the rules. And they weigh everything. But- if you book early, you can fly very cheaply.

i don't know about flights to London via Dublin but i spend 4 days in Dublin, i highly recommend the hop on-hop off bus get a 2 or 3 day pass an won't have to worry about transportation. a must see in my book are St patrick's cathedral, christ church cathedral, book of kells, natural museum of archaeology and History (bog bodies equal parts disturbing and interesting) Guinness store house, and kilmainham gaol. if you have time Dublinia is interesting but if you can't do it it's fine. i enjoyed just wondering around St Stephen's green and the other parks too. have fun! hope this helps.