Between January and March, and sometimes as early as December, thousands of gray whales migrate from the Bering Strait to the lagoons and bays of Baja's Pacific coast to give birth and start their calves in life. For reasons that remain completely mysterious, the calving whales and their newborn babies, rather than being shy of humans, appear to seek out contact with visitors, and the result is one of the most awe-inspiring wildlife encounters anywhere. You can experience it in a day trip or a longer overnight in the El Vizcaíno Biosphere Reserve, at Bahía Magdalena on the Pacific (about a 2-hr. drive from Loreto), Laguna San Ignacio (on the Pacific, near San Ignacio, a 4- to 5-hr. drive from Loreto or 2 hr. from Santa Rosalía), and Laguna Ojo de Liebre (near Guerrero Negro, 6 hr. from Loreto or 4 from Santa Rosalía).

What You'll See -- Gray whales are the favorite species for whale-watchers because they tend to swim and feed mostly in coastal shallows, occasionally resting with their abdomens on the bottom, while their close relatives prefer to frequent the deeper realms of the ocean. Whale-watching in one of Baja's lagoons is truly exciting -- at times, gray whales appear to be on all sides. In the lagoons and bays, gray whales are often so "friendly" and curious that they come up to the whale-watching boats and stay close by, sometimes allowing people to pet them.

You'll certainly experience the full scale of normal whale behavior at its most awesome. Watchers might be showered with a cloud of water from a whale spouting (clearing its blowhole) or might witness an enormous male spyhopping -- lifting its head vertically out of the water, just above eye level, to pivot around before slipping back into the water. Perhaps the most breathtaking spectacle of all is a breach, when a whale propels itself out of the water and arches through the air to land on its back with a splash.

Which Town? Which Tour?

Bahía Magdalena is the most easily accessible for a day tour from mid-Baja, but it's not as intense an experience as the other two lagoons -- it's much bigger, so whales are less concentrated, and they're less likely to come up to you. Still, it's one of Baja's classic whale sites, and you won't leave disappointed. It's easy to get here from Loreto, but three nearby towns, two on the bay's shore, also offer whale-watching tours. Puerto López Mateos, on the northern shore, is the closest town to the whales' calving areas. Accommodations and dining are limited to a few modest options, but several boat operators offer tours. Puerto San Carlos offers a more developed tourism infrastructure, with well-appointed hotels and restaurants, trailer parks, travel agencies, a bus station, and other services. Ciudad Constitución, the largest of the three towns, is 61km (38 miles) inland. It has a well-developed tourism infrastructure, with tour organizers that offer daily whale-watching tours during the season.

Laguna San Ignacio is accessed via San Ignacio, 74km (46 miles) to the northeast, a small town built by the Spaniards in the middle of a palm oasis, rich in Jesuit history. This lagoon is an excellent spot for whale-watching; in San Ignacio, the whales have a reputation for being especially "friendly" -- they'll seek you out more than the whales in Magdalena, occasionally allowing you to touch them. It's also a base for expeditions to some of the world's most amazing cave paintings, and a great spot for bird-watching, in whale season and outside. Baja by Kayak does combination whale-watching and bird-watching tours, 3 nights all inclusive for $995, out of Loreto. Ecoturismo Kuyima (tel. 615/154-0070; www.kuyima.com), on the shores of the lagoon, will put you up in comfortable, clean tents or cabanas, and feed you at its restaurant. Camping is $40 for a double tent, or sign up for an all-inclusive 4-day whale extravaganza that includes cabana accommodations, meals, three whale excursions, and tours of the lagoon for $495 per person.

Laguna Ojo de Liebre is accessible via Guerrero Negro, which sits on the dividing line between Southern and Northern Baja. It has a modest but well-developed tourism infrastructure in an otherwise industrial town (it's the site of the world's largest evaporative saltworks). The lagoon where gray whales calve and spend the winter has remained pristine, and has witnessed a remarkable comeback of this almost-extinct species. This lagoon is the farthest north and thus the most accessible for a whale-watching road trip from the U.S.; it's known for "friendlies" and high concentrations of whales. But Guerrero Negro is the most touristy-feeling of the lagoon towns -- upwards of 4,500 tourists a year come here in the 3-month season -- and there's not much there other than whale-watching. The most established tour company running boats on the lagoon is Mario's Tours (tel. 615/157-1940; www.mariostours.com); they charge $49 adults, $39 kids for 3 hours including a visit to a shore bird colony. Book tours through the Ejido Benito Juárez (www.elejidobenitojuarez.com), the community association that oversees the lagoon, $40 for adults, $30 for kids, or Malarrimo Ecotours (tel. 615/157-0100; www.malarrimo.com), 4 hours for $49 adults, $39 kids. Both can book you into very simple motel-like accommodations as well.

If whale-watching is a centerpiece of your Baja vacation, you'll want to plan at least one overnight at Guerrero Negro or San Ignacio, either on your own or with a tour. If you're going to Bahía Magdalena, Loreto may actually be the wisest base to choose, with its well-developed tourist infrastructure and good hotels and restaurants. From there, it's just a 2-hour drive to the bay, and en route you get a chance to view the spectacular desert landscape. All hotels and tour operators in Loreto offer day trips, for between $70 and $140, including transportation both ways, 2 hours on the water, and lunch; a taxi from Loreto to López Mateos costs 800 pesos. And you can even visit Magdalena in a day from Cabo San Lucas -- flying tours on Baja-based airline Aereo Calafia (tel. 624/143-4302; www.aereocalafia.com) fly 75-minutes to the bay, where you board a panga and spend 3 hours watching gray whales and humpbacks before returning the same day. This tour is $440, including air transportation, the tour, and lunch.

Getting There

Bahía Magdalena-- To get to Puerto López Mateos, take the only road going west from Loreto for about 121km (75 miles). When you arrive in the town of Insurgentes, turn right and continue 2.4km (1 1/2 miles) to the Puerto López Mateos exit. Turn left and continue 34km (21 miles) to Puerto López Mateos. To get to Puerto San Carlos, take the same road west to Insurgentes, and then drive south about 24km (15 miles) until you reach Ciudad Constitución. From Ciudad Constitución, take the exit marked PUERTO SAN CARLOS, and continue the remaining 63km (39 miles) to town. Both routes are well paved and maintained.

Laguna San Ignacio -- Right on Highway 1, the town of San Ignacio is 796km (494 miles) south of Ensenada and 271km (168 miles) northwest of Loreto. North-south buses stop at the gas station.

Laguna Ojo de Liebre -- Right on Highway 1, Guerrero Negro is 651km (404 miles) south of Ensenada and 416km (258 miles) northwest of Loreto. You can also fly there from Santa Rosalía on Aereo Calafia, or take an ABC or Transportes Aguila bus from all points north and south.

Should I Take a Tour or Hire a Boat?

You may get a better deal if you drive to the lagoon and head down to the local pier to hire a local panga operator. Expect to pay anywhere from $45 to $60 per person for a day trip with a local guide (plus a tip for good service). An organized tour can run almost double that price, but the services and respect for the whales that come at a higher price tag are worth it in most cases. It's always a good idea to check for licensed, experienced operators (they must have photo-ID credentials showing they are official tour guides) who know how to approach the whales with calm, caution, and respect for the environment. The most important thing about whale-watching is to enjoy it while practicing guidelines that ensure both your safety and the safety of the whales. (We've recommended several tour operators and organizations above.)

Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.