Image: Siena College via Flickr

There's no question that college is expensive, and tuition prices at some schools are downright astronomical.

But in some cases it's room and board—not tuition—that's the real money drain.

At UCLA, for example, housing in an on-campus dormitory costs more than tuition and fees.

And at University of California, Merced, students are opting to share McMansions in foreclosure-ridden communities rather than pay for on-campus housing, which can cost roughly double, according to an article in this weekend's New York Times.

College news website CampusGrotto has just released its annual list of the most expensive dorm rooms in America and, unsurprisingly, the most expensive room and board are found in New York, Boston, and on the California coast.

For the 2011-2012 school year, room and board prices increased 4% at public schools and 3.9% at private colleges, with average costs of $8,887 and $10,089, respectively, according to CampusGrotto.

Want to know where students pay the most to live? We've got the 10 most expensive college dorms here. Check out the full list of 20 at CampusGrotto.

Prices are for room and board for a double room with a meal plan for the 2011-2012 school year.