I visited this WHS in spring 2024. At first glance El Pinacate and Gran Desierto de Altar National Biosphere Reserve seems to be made up of two completely different components. By visiting the great Schuk Toak Visitor Centre (usually closed Monday to Wednesday, but not always) and its interesting lava trails + 5 kilometre dune trail (closed in summer and when temperatures get too high), you'll already get a good overview of the site (especially the Gran Desierto de Altar National component) and its OUV.

Each season in the Pinacate Biosphere Reserve has its attraction: autumn and winter are good for hiking, astronomical observation and fauna observation, although in winter it gets very cold at night. Spring is much more temperate and is really great for observing flowering flora and for bird watching. Summer tends to be very hot so it is the best time to spot more reptiles, however, the dune trail is closed due to high temperatures.

After being quoted ridiculous prices for day tours from Puerto Penasco (apparently it is very easy to get there from the US, so tourist services are catered (and priced!) mostly for Americans), I decided to follow Els' footsteps and booked a one night-two day camping tour (Noche de Estrellas en El Pinacate) with the excellent Pinacate Tours from Hermosillo. Departure from Plaza Emiliana de Zubeldia is at 6am sharp in a white van. I paid a bit extra for a solo tent, sleeping bag and inflatable mattress for extra comfort). The van stops twice before getting to the site proper, once at around 08:30 at Restaurant Elba in Santa Ana and once at around 14:00 at Sonoyta for lunch and a toilet break. Within the WHS, the only place with toilet facilities is the Shuck Toak Visitor Centre.

Although visiting this WHS alone is possible with a high clearance vehicle (4x4 not needed although quite useful especially if it rains before), logistics of getting the required permit and getting the go ahead to visit certain areas due to land disputes, plus the real risk of not finding your way once inside the reserve, require quite some skills and I'd suggest plenty of water just in case. Away from the main road and visitor centre, mobile phone signal is very weak or non-existent.

Our first stop inside the El Pinacate reserve is at the Sahuaro Danzante, a peculiar shaped arborescent Saguaro cactus. Our next stops for the day were at the mined cinder cone of La Laja, the spectacular El Elegante crater, with a diameter of 1,600 metres and depth of 250 metres, before stopping at the camping area known as El Tecolote (almost no light pollution on a clear day, so our accompanying student astronomer could easily point out the different stars, planets, constellations, satellites, etc. using her laser light after our BBQ with sandwiches, sausages and marshmallows).

El Pinacate has two kinds of volcano, a composite volcanic mountain that began erupting before 2-3 million years ago and ceased to erupt around 1 million years ago, and a distributed monogenetic volcanism that scattered nearly 500 cone volcanoes across the mountain and surrounding desert starting before the mountain was extinct. The monogenetic volcanoes, also called "cinder cones", were each built in a single, continuous, short eruption from its own unique magma. A few of the cone eruptions ended with magma mixing into ground water to create steam explosions that blasted large craters into the landscape, creating "maar calderas" far larger than any of the monogenetic cones.

The following day, just before sunrise we hiked up Cono Mayo for about 20 minutes to enjoy sunrise and the panoramic view over the Sonoran desert. After breakfast, we packed our tents and proceeded to the Cerro Colorado crater, a tuff-cone and a hydrovolcano without a maar caldera. After that, we headed towards the Schuk Toak Visitor Centre (the UNESCO WHS plaque and inscription certificater can be found here) and hiked to the dunes which are surrounded by mountains on one side and the sea on the other. After about 3 hours, we headed to the Puerto Penasco Malecon before driving back to Hermosillo and arriving around 11:30pm.

Overall, I was very happy with the whole tour and managed to observe quite a lot of flowering flora (some cacti flowers are only visible just before sunrise) and avifauna (ex. Gila Woodpeckers, Leconte's Thrashers, American Kestrels, Greater Roadrunners, etc.). I also managed to spot several butterfly species and caterpillars in the Gran Desierto de Altar dunes, as well as desert iron-claded beetles, darkling beetles, long-nosed leopard lizards, desert iguanas, chuckwallas, and a few round-tailed ground squirrels, desert cottontails and a black-tailed jackrabbits. The highlight species I managed to spot during my short visit was the Gila monster, a large venomous lizard.