Q. What is it supposed to be on the show?

A. The interior of the local country club, on the golf course.

Q. Where is it supposed to be on the show?

A. They show an establishing aerial shot of the real Pelican Hill Country Club, in Newport Beach.

Q. When did we see it on the show?

A. In Episode 4 (of season one), "The Debut", we see Ryan and Seth enter through a lobby, then turn into a ballroom, where a woman is leading the students in a rehearsal for the upcoming Cotillion dance. Ryan meets Milissa, and is introduced to Anna for the first time. Ryan dances with Anna, and Summer reluctantly dances with Seth.

Q. What is it actually in real life?

A. A hotel lobby & ballroom, but not in Newport.

Q. Where can I find it in real life?

A. Although the exterior and entrance shots of the previous Cotillion scenes were shot at the country club location (Trump National Golf Club), these interior shots of the dance rehearsal scenes were actually filmed inside the Manhattan Beach Marriott Hotel at 1400 Parkview Avenue, in Manhattan Beach, CA

The hotel is located right next door to (west of) the studio where The O.C. is filmed.

Here is a map link to the exact location.

And here is a link to the hotel's official website.

(The hotel's golf course was seen in another episode. And the tennis courts next door to the hotel were seen in yet another episode.)

Q. How the heck did you figure out where it was?

A. I found this one via a tip from a fan, Fabian (of Switzerland), who emailed me and alerted me to it. He also directed me to the Marriott's official website, where it was easy to match up photos of the hotel with the episode's screenshots.

Most notably, the unusual lamps in the Marriott hotel's lobby were a perfect match (see the middle photo above), as was the yellow & white-striped wallpaper in the hotel - and in another scene, you can see the hotel's golf course out the window behind Ryan (see the photo to the right).