Whale shark encounters rank near the top of any diving bucket list. With a head like the hood of a Ford, dizzying dots and tiny eyes incongruous with its sheer mass, this endangered animal is the largest fish in the oceans.

The irony for divers, of course, is that you’re most likely to find whale sharks near the water’s surface with a snorkel clenched between your molars instead of a regulator. But it doesn’t make the experience any less sensational.

Whale sharks live all around the world in cooler waters. If you're looking to check this experience off your diving bucket list, each of the following destinations rank among the best spots to come face-to-face with these docile beauties.

1. Holbox, Mexico and Isla Contoy, Mexico

Local fishermen in Holbox, an island off the Yucatán Peninsula, paid no attention to the whale sharks that frequented their waters every summer, since they aren’t a food source. But when tourists who’d been swimming with the creatures in Africa started spreading the word that whale sharks were to be found in Holbox, the whale sharks became one of the town's prime attractions. Nearby Isla Contoy has emerged as a popular gathering spot over the last several years.

When to Go: Mid-July through the end of August for the best encounters.

2. Gladden Spit, Belize

Pull out your moon chart! Whale shark encounters flow with the spring lunar cycle in the Gladden Spit, when snappers spawning draws in the whale sharks. Your best bet for an encounter is the three days before or after the full moon. Boats have a 90-minute window in which to catch the whale sharks. Boats must stay 50 feet away from the animals while divers and snorkelers are required to maintain a 10-foot distance. Only eight tourists are allowed per guide. Flash photography isn’t permitted to protect the animals. Don't worry: diving with the mammoth creatures is a mind-blowing encounter worth every bit of stringent rule-following.

When to Go: Plan your visit between April and May, when the snapper spawning lures the whale sharks to Gladden Spit.

3. Tanzania

Want an experience few divers will ever have? Then head to the waters around Mafia Island, Tanzania for your whale shark encounter. Usually migratory, the whale sharks around Mafia stay in these waters year-round, which scientists think is due to the area’s abundance of food like plankton and shrimp. Swimming with whale sharks at this under-the-radar destination is not a year round activity, however, as they reside far off land in deeper waters for part of the year.

When to Go: October to February is prime time when the whale sharks move to shallow waters.

4. Honda Bay, Palawan, Philippines

Everyone already knows about Donsol to the north, but for a different kind of whale shark encounter head to Palawan’s Puerto Princesa. Dive boats scout for whale sharks between dives or on custom trips to see the animals and then hustle you into the water with a snorkel and mask to take in the spectacle. You can go through a dive shop to “schedule” an encounter, and local guides — often fishermen — also take visitors to sea in traditional outrigger bangkas to spot whale sharks.

When to Go: The best conditions occur April through October.

5. Utila, Honduras

It can be hit-or-miss here, but impromptu snorkel sessions between dives are when nearly all whale shark encounters occur in Utila — one of the few places in the world where the animals can be spotted year-round. The deeper waters off the north side of the island are where the animals are most often seen, and guides look for the cues of water boiling with jumping tuna and flocking seabirds.

When to Go: Year-round.

6. Australia

Whale sharks gather to feed in the Ningaloo Reef, a UNESCO World Heritage site, off of the country’s western coast. They gather in the water in such high numbers that the region boasts that 97 percent of whale shark tours result in an encounter. Swimmers must stay 12 feet from the whale sharks at all times, and 16 feet from the tail. Don’t worry about the distance—12 feet is plenty close when you’re talking about a 40,000 pound fish!

When to Go: March to June typically sees the highest concentration of whale sharks in Australian waters.

7. Cabo San Sebastian, Mozambique
   Home to one of the largest concentrations of whale sharks in Africa and pristine coral reefs unpressured by mass tourism, Mozambique is one of those swoon-worthy, off-the-beaten-path destinations that wins you serious bragging rights among your buddies. Most encounters with the whale sharks here happen when the animals are feeding on plankton and krill near the surface. Cabo San Sebastian's reefs (66 to 131 feet deep) are where they’re often seen, with most animals around thirty feet long.

When to Go: November through February offers the best conditions.

More Animal Dives:

• Scuba Diving with the Planet's Deadliest Animals
• 25 Best Shark Diving Destinations
• Best Big-Animal Scuba Diving Destinations