Daniel Terdiman/CNET

Update (Sunday, 12:20 a.m. PT): The answer to Saturday's challenge -- which 57 people got right -- is the Pillar Point Air Force Station, in Half Moon Bay, Calif. Thanks to everyone who played, and to all, please come back for Sunday's challenge.

Welcome to the Road Trip Picture of the Day contest. This is your chance to win some cool prizes as you test your skills at recognizing pictures.

Each day, I'll be posting a new photograph from my various travels, and your job is to try to correctly identify it using any means at your disposal. Throughout Road Trip 2012, which will take me through California, Arizona, Nevada, and Oregon, there will be a new challenge each day, and the opportunity to win some great prizes. I will update each day's post with the answer sometime after the entry deadline -- usually the same evening, although occasionally the next day or shortly afterwards -- so please come back later if you'd like to know the correct answer.

Now, on to today's challenge.

If you know what this is and where it's located, please send me an e-mail with both pieces of information (to daniel*dot*terdiman--at--cbs*dot*com) by 6 p.m. Pacific time today.

Please note: To be considered, you must include the phrase "Picture of the Day challenge" in the subject line of your e-mail. No other methods of entering are guaranteed to be considered.

And please forgive me if you don't hear from me if you're not the winner. I get dozens of responses each day. Also, I've turned off comments because otherwise people will post the correct answers there. I hate to shut down discussion, but I want you to figure out the answer on your own.

The giveaways

This year, I'll be giving both a weekly prize and one grand prize at the end of my Road Trip project. Here's how it will work:

For the weekly prize, I'll pick a winner at random from among all those who correctly identified one of that week's daily challenges. You get one entry into this drawing for each correct entry you submitted that week.

For the grand prize, which is a complete set of GoPro camera gear, the winner will be the person who answers the most daily challenges correctly during the entire project. So there's definitely an incentive to play every day and to answer correctly as often as possible. Be warned: last year, the winner got 67 out of 70 possible correct answers, and several others got more than 60 right, so the competition for the grand prize will be stiff.

Given the constraints of the work I'll be doing on Road Trip, I have to minimize the complexity of the Picture of the Day challenge, so if you want to accumulate right answers and compete for the grand prize, you must use the same e-mail address and name each time. If you use a different name or e-mail address, your answers won't be counted together.

For complete information and rules about the Picture of the Day challenge, please click here.

Good luck today, and throughout the summer.

The disclaimer: NO PURCHASE NECESSARY TO ENTER OR WIN. MUST BE A LEGAL RESIDENT OF ONE OF THE 50 UNITED STATES OR D.C., 18 YEARS OLD AND AGE OF MAJORITY OR OLDER IN STATE OF RESIDENCE AT DATE OF ENTRY INTO SWEEPSTAKES. VOID IN PUERTO RICO, ALL U.S. TERRITORIES AND POSSESSIONS AND WHERE PROHIBITED BY LAW. SWEEPSTAKES ENDS 11:59:59 PM PT ON 8/10/12. SEE OFFICIAL RULES FOR DETAILS.