Scotts Cheap Flights has found some round-trip airfares from Houston to Europe in the $400 range. Travel up through May 2018, with some also in August 2018. Mostly Delta, some Air France and Air Canada.
European destinations from Houston include Brussels, Frankfurt, Geneva and Munich. Of course, you can take a European UCC (Ultra low-cost carrier, like Ryanair or Easy Jet) from any of those cities to wherever you want to go in Europe.
Other departure cities are also available, including Chicago (take Southwest or American non-stop from Austin to Chicago), Denver, Las Vegas and Washington, D.C.
You can fly to Dublin, Ireland, for as little as $427 round-trip on several Star Alliance airlines.
Winter travel, from a variety of U.S. cities, on Air Canada, Lufthansa or United.
While you may not want to spend a lot of winter days in Dublin, remember that it is the hub city for ultra-low-cost Ryanair. Ryanair flies to numerous European destinations, sometimes for just a few dollars per ticket plus miscellaneous add-on fees.
Some of the least-expensive flights from the United States to Europe land in Dublin, Ireland. A smart idea is to spend a couple of days in Dublin, then continue on ultra-low-cost Ryanair to your final destination somewhere else in Europe.
This blog post lists 8 fun (plus one not-so-fun) activities to do while you are in Dublin.
The not-so-fun activity is the expensive cab ride into downtown. I’ve personally experienced a couple of the others (think Guinness brewery), and will be taking the list along on my next visit.
A ninth fun activity, not on the list, is a poetry pub crawl. This starts in the early evening and has a group following a poetry-reciter from pub to pub…great fun!