San Diego Area
Black's Beach (Torrey Pines Scenic Drive, La Jolla): If you like hanging out naked and you like beaches, this is the place to go - the beach is wide and flat, the waves are great, and there's always a decent amount of fit naked men! The north trail takes you straight down from the parking area to the gay section of the beach, but isn't for the faint of heart - if you have a fear of heights, take the south trail down to the beach, and you'll have the added bonus of walking past all the hot naked straight guys before you get to the gay section of the beach. Put your towel down near the high tide line, and you'll enjoy a parade of guys walking back and forth along the beach...or camp out by the trail near the cliffs if you're looking for a little more action. The beach patrol regularly drives up and down the beach, so make sure to keep an eye out if you're engaging in anything more friendly than a handshake.
Pet peeve: I've been to Black's on occasions when it seems like 40% to 50% of the guys on the gay end of the beach are wearing trunks - WTF??! If you're going to go to the trouble of hiking all the way down to a nude beach, you should at least have the courtesy to get naked....geez. Pussies.
Weather advice for those of us from the desert: It's generally a great time to go to Black's any time the temperature is in the 70's or above. The beach is generally overcast in the morning during the summer, but the clouds burn off around noon - so I usually wait until about 1pm to hit the sand. Also, don't let the temperature/wind in the parking area fool you - it's generally warmer and less windy down on the beach than it is up on top of the cliffs.
Aqua Day Spa (4637 Convoy Street, Kearny Mesa): This is the only Korean spa that I know of in the San Diego area, and I used to come here occasionally to soak and steam after a day at the beach. The place is small (the locker area is about the size of my bathroom at best), and only has the usual amenities (steam, sauna, whirlpool, cold plunge), but it gets the job done if you want a good sweat. I've been reading on Squirt.org that management has been cracking down on sexual activity - so if you go, be on your best behavior.
Orange County Area
San Onofre State Beach (Basilone Road exit, San Clemente): I'll be honest - in many respects, this is a crappy beach. It's rocky, most of the sand is covered with desert scrub, there's fewer guys here than at Black's, everyone is spread out....but let's just say it's more active. Finding the beach is a little tricky the first time - follow the signs to San Onofre State Beach from the Basilone Road exit on I-5, pay the $15 day fee at the guardhouse, and continue driving south all the way down to the Trail #6 parking area (which is as far south as you can go). Head down the trail to the beach, take a left once you hit the sand and continue south - after about a 7-minute hike, you'll come to a fence which separates the public beach from the Camp Pendleton Marine Corps property (yep, the nude part of the beach is actually on the base). The straights hang out in the area just south of the fence - for the gay section, keep on hiking further south (I like to set up about 10 minutes further down the trail where there's a little more sand). It's not uncommon to see creepy guys at Onofre who do nothing but walk back and forth along the trail and follow unsuspecting guys up into the canyons off the trail (I went into a canyon once to take a piss, and had two old guys on me in seconds wanting to blow me - so now, I just piss out in the open). Guys are more likely to get naked here than at Black's, and it's definitely more playful - so it's worth a visit.
Nice to know: Occasionally, the Marines will be doing practice maneuvers at the beach - so the nudists are forced to move north of the fence and put their clothes back on. I've read on the internet that they used to issue tickets for being on the base property, but that hasn't been my experience in the last couple of years that I've been going to Onofre.
I-Spa (2332 Barranca Parkway, Irvine): After a day at San Onofre, I like to head up the highway to Irvine and spend an hour or two at I-Spa, steaming the sunscreen out of my pores and having a good soak. Even though it's not the cruisiest spa, it's one of the cleanest and best maintained spas I've been to. It has the standard amenities, but with an additional whirlpool and the added benefit of windows looking out to a small outdoor garden from the wet area. Despite the fact that there isn't a lot of cruising at I-Spa, I regularly see other gay men here (as well as hot straight guys and the occasional military guy), so there's usually something to look at while you're soaking and steaming.
Los Angeles Area
While there aren't any nude beaches in the LA area that I'm aware of, this is Korean spa heaven, so there are a lot of choices if you're in the area...
Century Day & Night Spa (4120 W. Olympic Boulevard): Century is probably the cruisiest Korean spa out of the bunch. There's a lot of horny guys that frequent this place, and the gay men easily outnumber the poor straight Korean guys (who are probably exposed to a lot more than they would ever want to see). The one drawback is that they give out regular-sized bath towels to the patrons, so unfortunately, a lot of guys stay wrapped up most of the time. The wet area is large, and includes a steam room, mist sauna, regular sauna, cold room, cold plunge, whirlpool, tea bath (smaller, hotter, stinkier whirlpool - but it's good for a discreet grope session). There's an outdoor patio just off the wet area, which is a good spot for cooling off after a good sweat - and there tends to be a lot of activity out there too. Down the hall from the wet area is the clay sauna and the marble sauna - and upstairs, there's a meditation room with 3 beds that looks down over the wet area. The whirlpool is a great place to sit and check everything out - I like to sit naked on the back edge of the whirlpool, dick out and semi-stiff, watching all the activity - from that vantage point, you can see all of the guys showering, cruising in and out of the saunas, checking out the patio area, and even see what's happening upstairs in the meditation room.
Wi Spa (2700 Wilshire Boulevard): Wi spa (I know, funny name) isn't anywhere as cruisy as Century, but I like the fact that there are no large towels here, so everyone pretty much has to hang out naked (and that's the way it should be at a spa). The wet area has the standard stuff - whirlpool, hot whirlpool, cold plunge, steam room, sauna - plus, an alcove with a heated stone floor for sleeping. Wi tends to attract a lot of families, so you'll occasionally see young kids in the wet area with their fathers - even at odd hours. I've done the overnight thing here a couple of times on a weekend (they have a dark sleeping room with recliners), and noticed that it's not uncommon to see hot drunk gay guys here at 2:00 a.m., steaming out the toxins before heading home from the clubs.
Beverly Hot Springs (308 N. Oxford Avenue): Beverly Hot Springs is kind of funky - but in a good way. Before we get to the funkiness, the key thing to know about Beverly is that their water source is directly from an artesian well, and makes your skin feel incredibly silky (as opposed to dried out from the chlorine which is often the case at other spas). The men's spa is on the second floor of the building, and the wet area is designed to look like a dimly-lit grotto of sorts. The spring-fed pool is comparatively large; there's also a cold plunge, a small steam room (skip it if you have personal space issues), and a decent-sized sauna. In addition, there's a relaxation room off to the side of the wet area, with lounge chairs for hanging out naked between soaking and steaming. While more expensive than the other spas in town and only semi-cruisy, the place is worth checking out for the wonderful qualities of their artesian spring water.
Wilshire Spa (3440 Wilshire Boulevard): Wilshire Health is kind of funky - but not always in a good way. The maintenance (and decor) is kind of sketchy, the whirlpool and sauna are way too hot to be enjoyable, and there's this strange rock water feature in the corner that I'm not sure is ornamental or if you're actually supposed to soak in it (I've seen guys sitting in it, so I'm assuming it's intended for that purpose). Regardless, this place can be cruisy at times - especially the sleeping room. Finding it is a bit of a challenge - while the address is on Wilshire Boulevard, the entrance is on the side street (Mariposa Ave.), and the sign says something like "Health Club" instead of "Wilshire Spa" (which is the name on their website and all of their promotional materials).
Lions Spa (4551 W. Pico Boulevard): This is actually more of a warning than a review - this place is a dump. Avoid it.
While there is a nude beach in SF - Golden Gate Beach (Lincoln Boulevard) - it's always been too cold whenever I've been to San Francisco to check it out and get naked! Maybe someday....
Kabuki Springs & Spa (1750 Geary Boulevard): I always make time for Kabuki when I'm in SF. It has a different vibe than the Korean spas - Korean spas tend to be much more social, while Kabuki is more about silence and tranquility - but it's a beautifully maintained facility with great decor, and there's always an abundance of naked men. Two things to be aware of: 1) They don't have separate men's and women's areas, so they alternate days of the week for each gender - the men's days are Monday, Thursday, and Saturday; and 2) They limit the number of men using the spa, so you may have to wait to get in. Instead of a whirlpool, there's a shallow soaking pool; they also have a cold plunge, large sauna, and decent-sized steam room. While they provide large bath towels for patrons, most of the guys are comfortable letting it all hang out. Despite this being San Francisco, cruising is minimal - partly due to the fact that the spa attendants are constantly in and out of the wet area - but regardless, I always enjoying spending some naked time here.
Bay to Breakers Race: While not a spa or a beach - the annual Bay to Breakers race (held in mid-May) is a terrific event and there are always a number of naked runners on the course. Feeling brave? Strip down to your jock (or less) and have a run through San Francisco!