There's yet another study that shows that 2015 is the year for a European getaway.
The average cost of a weeklong trip in Europe this summer has decreased by 11% since last year, according to TripAdvisor. Depending on where travelers go, the cost could be as much as 25% cheaper.
The most affordable destination on TripAdvisor "TripIndex" is Istanbul; the site estimates the cost of a week there this summer at $1,877. The most expensive destination, on the other hand, is Zurich, at an estimated $3,236 for a week.
The U.S. dollar is the strongest it has been against the euro and British pound in years, making Europe's many sights tempting for travelers.
Of the 25 European destinations that the travel booking site analyzed, the least expensive for flights this summer is Reykjavik, at $1,086, and most expensive was London, at $1,763.
Top European destinations, estimated one-week trip in summer 2015
Istanbul - $1,877
Bucharest - $1,894
Krakow - $1,983
Budapest - $2,028
Prague - $2,074
Athens - $2,087
Brussels - $2,111
Berlin - $2,150
Lisbon - $2,171
Stockholm - $2,184
Oslo - $2,203
Dublin - $2,229
Moscow - $2,275
Helsinki - $2,304
Copenhagen - $2,347
Vienna - $2,384
Barcelona - $2,393
Rome - $2,521
Amsterdam - $2,693
Paris - $2,729
Dubrovnik - $2,766
Edinburgh - $2,806
Reykjavik - $2,890
London - $3,183
Zurich - $3,236