If you know what this is and where this photograph was taken, you could win a prize in the Picture of the Week challenge.

That's an odd hillside, with some very strange portholes built into it. Is it a Hobbit house What is it actually, and where is it located

If you know, you could win a prize in the CNET Road Trip Picture of the Week challenge.

If you have the answer, please e-mail it to me no later than 6 p.m. PT Friday (to daniel--dot--terdiman--at--cnet--dot--com, and PLEASE include "Picture of the Week" in the subject line). I'll choose a winner at random from among everyone who sends in the correct answer by the deadline. Please forgive me if you don't hear from me if you're not a winner. I get dozens of responses for each challenge.

Also, I've turned off comments because some people would post the correct answers there. I hate to shut down discussion, but I want you to figure out the answer on your own.

One caveat: no individual can win more than two prizes. However, now that it's 2011, I'm resetting the tally, and past two-time winners are eligible again.

The Road Trip Picture of the Week challenge takes place each Thursday, and the photos could come from anywhere, not just Road Trip 2010 locations. Plus, they might be related to stories I've written in the past. So, please have fun playing today, and then come back each Thursday.

For most of last summer, Geek Gestalt was on Road Trip 2010. After driving more than 18,000 miles in the Rocky Mountains, the Pacific Northwest, the Southwest and the Southeast over the last four years, I drove 5,266 miles this summer looking for the best in technology, science, military, nature, aviation and more throughout the American Northeast. You can follow me on Twitter at @GreeterDan and @RoadTrip and find the project on Facebook. And look for Road Trip 2011 coming this summer.