Put your PTO days to good use, and book a flight to one of the most bustling cities in the U.S.

Better yet, be a savvy traveler and book a flight to one of the top budget-friendly destinations.

Travel-booking site Kayak has launched a "Holiday Travel Hacker" guide for 2017/2018 to help you do just that. It outlines the biggest trends for New Year's, the best times to book holiday flights, and the most affordable destinations in the U.S. and abroad.

Here are the top sites around the U.S. and Canada. The cost of flying to one of these hotspots is lower than median airfare for other North American flights.