I visited this WHS in January 2022 focusing on the Islas Marietas National Park. Depending on the tide and weather conditions, the boat tour companies with the most expensive prices from Puerto Vallarta, Jalisco (full day trips) and Punta Mita, Nayarit do half day trips including a stop and swim in the instagram famous hidden beach, and two more snorkelling and swimming points along another beach of the Marietas Islands.

Make sure to allow more than one day just in case weather isn't good, and when booking at least a day in advance, stress that you would like to visit the hidden beach at the earliest time in the morning to make sure the daily limit isn't reached. Just outside the rocky outcrop leading to the hidden beach from the sea, national guards patrol the area to make sure only visitors with 2 appropriate bands on their hand are given helmets and lifejackets to swim to the hidden beach. From the time you start swimming to the beach you're allowed around 30 minutes and then you have to swim back to your boat. We booked a private tour and knowing that most tours leave the hidden beach as their second or third stop during the Islas Marietas tour, we specifically asked to head straight there, ignoring the whales and dolphins other boats had spotted far out at sea, in favour of getting to the hidden beach first. Drones are not allowed any longer to protect the birds so we had to delete the only video taken but managed to save a quick photo on our phone at least.

Most boat tour companies don't guarantee swimming at the hidden beach, and if you're not given two wristbands upon boarding the boat it means you won't visit. There was quite a swell when we visited and high tide meaning that our short swim to the hidden beach was quite adventurous and it was a good thing we had helmets as I scratched my head with the rocks going in as there was very little clearance. We were overjoyed though to be in such a heavenly place all alone except blue-footed boobies, frigate birds, gulls, terns and turtles. This rigidity in visits is having a very positive effect not only on the birds but also on the marine life as turtles, rays, dolphins and whales are thriving around the islands since the beach is managed in a eco-friendly manner. By the time we left and especially an hour after, there was a queue of boats waiting for their turn to visit. In the meantime, we were very lucky to spot a humpback whale and its calf playing and feeding just off the coast of the Islas Marietas which was the cherry on the cake. Although the photos and videos I took were the best I ever took on a boat trip (after filming sperm whales in the Azores and humpback whales in the Oaxaca coast), the moments I didn't manage to capture with impressive out-of-the-water leaps will forever remain in my memory as uncaptured moments on camera. Towards the end of our trip, before heading to the harbour, we were escorted by a pod of six to eight humpback whales which we continued to spot from land.

The snorkelling is really good in the especially clear waters of the islands. At the second beach, there's also a high ladder leading over the 90 degree cliff from the beach, although you need to get special permission and a tour with a naturalist guide to climb it. Another cool way to visit is by kayak, chancing a close encounter with the gentle giants at sea, present mainly in the winter months between December and April (mostly humpback whales but occasionally also blue whales and orcas). During the tour we did a quick loop around the islands, passing close to two natural rock arches en route. The marine life and nature around the Marietas Islands National Park is top notch and the boat tour experience and adventure swim reminded me a bit of the swimming trips with seals and marine fauna at the Galapagos Islands. We'll definitely make an extra effort to visit other locations of this WHS in Baja California on our next visit to Mexico, trying our luck once again with blue whales or orcas.