Southern California divers can be a bit vain when they’re abroad, relentlessly comparing exotic dives to sites at home. Those that scuba dive in San Diego may be the worst — not surprising, given that they have access to some of the world’s best diving on any given day. Happily, this bounty is available to all, including thousands of divers who visit the area each year.

California Classic: Kelp Diving

The kelp forest is often the first thing that comes to mind when California diving is mentioned; in San Diego, the choices are unmatched. La Jolla Cove, accessible by shore entry, requires a bit of parking savvy and patience, since the area is often crowded with swimmers, snorkelers and tourists. A bit of persistence can pay off in a big way, however, since divers can be immersed in a shallow kelp forest — 35-plus feet — within minutes.

While the viz might not be the best, this site offers divers a good chance to get up close and personal with nesting garibaldi, sea lions, harbor seals and even seven gill sharks.

Nearby sites at the Point Loma kelp beds — most lie between 45 and 120 feet — are reached by day boat and offer a slightly different kelp experience. This area is bathed with cold, nutrient-rich water that supports an incredible variety of life. The lush rocky reefs are a colorful riot of gorgonians, sponges and bryozoans; careful inspection of crannies and crevices will reveal moray eels, lingcod and cabezon. Point Loma’s phenomenal invertebrate density has also delighted many a nudibranch fanatic: It isn’t unheard of to see 20 different species of nudis on a single dive.

When divers are looking for warmer water and better visibility, an easy overnight run to San Clemente Island can transport them to a completely different kelp setting. At this southernmost of the California Channel Islands, purple hydrocoral and fiery-red gorgonians dot reefs, while torpedo rays and soupfin sharks patrol towering kelp forests in clear blue water, with many popular sites between 40- and 100-plus feet.

Exploring Wreck Alley

Wreck enthusiasts are thoroughly spoiled in San Diego, where a collection of purpose-sunk ships forms world-famous Wreck Alley. The highlight of this artificial-reef system is the extraordinary HCMS Yukon, a 366- foot Canadian destroyer sunk in 2000 that lies between 70 and 105 feet of water. The ship went down in rough seas the night before its intended reefing and lies on its port side, which can be a bit disorienting, and surge and current are more common than not. Divers are undeterred, however, as its considerable superstructure includes easily recognizable structures. The bridge, crow’s nest, davits and smokestack are layered with plumose anemones, bright corynactis and clusters of majestic giant metridiums, providing incredible photo opportunities. Schools of blacksmith gather above the wreck, and divers often find themselves surrounded by fish during their ascent.

Locals and visitors alike adore the close-by Ruby E, a 165-foot Coast Guard cutter-turned drug smuggling vessel that was sunk in 1989. Its smaller size and slightly shallower depth — 60 to 85 feet — mean it’s easier to fully examine on a single dive; its upright structure is so thickly encrusted with red gorgonians and pink corynactis that the ship is commonly compared to a Rose Bowl float. It’s easy to safely inspect its wide-open bridge and wheelhouse, though divers often get too distracted by the brightly colored greenlings, rockfish and California scorpionfish on its decks to bother.

Pinniped Pandemonium

While pinnipeds can be encountered at any California dive site, there’s one surefire way for divers to immerse themselves in sea lion soup: Take a day trip over the border to Mexico.

Twenty miles southwest of San Diego are the Islas Coronados, the northernmost of which contains one of the liveliest sea lion rookeries in the area. The dive sites are shallow, protected and generally offer the clearest, warmest water accessible by San Diego day boat. While many sites extend well beyond recreational depths at Los Coronados, divers frequently spend the entire day in less than 40 feet of water, watching the antics of the comical mammals that live here year-round. Friendly, fat harbor seals are also regularly spotted in this area.

Muck and More

San Diego also has a more obscure underwater attraction: critter diving. Submarine canyons immediately offshore dip abruptly to depths of more than 600 feet, providing a density of marine life that is matched by few other places in California. La Jolla Shores — part of the La Jolla Underwater Park — is one of the epicenters of this phenomenon. The sandy walls and tangled kelp detritus of this popular shore-diving spot don’t look like much at first glance. But veteran divers know the marine life found here includes red and two-spot octopuses, juvenile fish, shrimp, blennies and an ever-changing and multihued array of nudibranchs.

Critters aside, the close proximity of these submarine canyons means that divers can see almost anything at any time. Sightings of bait balls, molas and various sharks are not uncommon. Fortunate divers might witness a rare market-squid mating run or a migrating gray whale. Even when conditions are less than optimal, there’s plenty of reason to go diving: The same springtime upwellings that bring frigid water to the coast also bring jellyfish and colorful pelagic invertebrates of all shapes and sizes.

On nondiving days, incredible marine life can also be easily viewed. Sea lion and harbor seal colonies populate the rocks and beaches near La Jolla. Gray and blue whales and pods of dolphins can often be spotted from the shoreline, and whale-watching boats offer the chance to get even closer.

Southern California Itinerary

>>Hire a local guide at San Diego Divers to help you navigate La Jolla Shores, one of Southern California’s best muck dives. Small red octopuses, nudibranchs and yellowfin fringehead blennies are common.

>>Then head into town to Point Loma Seafoods for an early dinner (watch the time; they close at 7 p.m.) of incredibly fresh seafood, including Baja-style fish tacos.

>>Board the MV Horizon on the adjacent dock for an overnight run to San Clemente Island. Spend the day aboard the Horizon enjoying the beautiful kelp forests of San Clemente, where you can watch harbor seals and torpedo rays glide through blue water. Breakfast, lunch and dinner are included. Head back to San Diego, and get a good night’s sleep.

>>After breakfast at the Mission in Mission Bay, check in with Waterhorse Charters for a two-tank dive charter to Wreck Alley. Dive No. 1 will visit the behemoth HCMS Yukon, and dive No. 2 will take you to the pretty Ruby E.

>>Spend the afternoon visiting the Scripps Aquarium in La Jolla.

Need to Know

>>When to go: Midsummer through winter (July to January) generally offers the best visibility, with fall providing an optimal chance for calm seas.

>>Dive Conditions: Water temps at depth range from 48 to 62 degrees F year-round, with the coldest water in early summer in San Diego and the warmest water in late summer/early fall at San Clemente island. a drysuit or 7 mm wetsuit with hooded vest is recommended year-round.

>>Operators: San diego divers (sandiegodivers.com) offers guided local dives starting at $80. Horizon Charters (horizoncharters.com) runs one-day/one-night trips to San Clemente island starting at $180. Waterhorse Charters (waterhorsecharters.com) runs two- and three-tank trips to Wreck alley (advanced certification is required) starting at $99.