Dublin- The capital and most populous city of Ireland.The English name for the city is derived from the Irish name Dubhlinn, meaning "black pool". Dublin is situated near the midpoint of Ireland's east coast, at the mouth of the River Liffey and the center of the Dublin Region. It is also one of the most affordable airports in the EU. It's a great access point to the UK and Western Europe. There is this wonderful little gem of an airline called Aer Lingus who travels from major US cities to Dublin for a decent rate.
Another great thing about DUB is that they also service the smaller, cheaper airlines that are great for traveling around Europe. Airlines like Ryan Air and Jet Blue, often use smaller, more remote airports to save on taxes and fees so you the traveler will save as well, but Dublin is one of the few LARGE hubs. This makes it very easy to fly in on an affordable roundtrip ticket and then hop to your final destination for a steal.
Barcelona- the capital of Catalonia and the second largest city in Spain. I have NO IDEA why it is so affordable to fly here. It's a city filled with amazing art and architecture. Plus some beautiful beaches! Either way, it's the traveler's gain, so take advantage. Especially if you're looking to hop down to Morocco, which can easily be done.
Now BCN is as large of a hub, but it does offer another alternative: Rail access. If you have always dreamed of roaming the trains of Europe, this is a great jumping point. From Barcelona it is just an overnight trail to amazing destinations like Paris or Roma.
Frankfurt am Main- I know what your thinking ("WHAT?! How?? and No way!"), but read me out! While it is only the 5th largest city in Germany, Frankfurt is the economical mecca of this strong EU nation. With all this financial business going on, it makes sense that flights are easier to find and may cost a little less. The airport connects directly to the rail system and the city is a great launching area for the romantic countryside.
San José- The capital of Costa Rica is a great link into the Central American jungles. Travel through central and south America can be spotty at best, but by flying over some of the more hostile areas you can easily link up with a more reliable bus system. Flights here can very throughout the year, but most affordable is during rainy season. Don't let a few sprinkles dampen your thirst for adventure!
As far as Asia goes, it gets a little more tricky. The single largest market for Asia-USA service is to/from/via Tokyo/Narita, followed by Hong Kong. Depending on time and cost, you can also price out travel to Canada. Air Canada has an extensive network of Asia-Canada service including numerous Toronto non-stops aside from their Asia gateway city of Vancouver. Taipei also offer some attractive carriers who are generally seen as budget friendly: China Airlines and EVA Airlines.
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