This is a beautiful lagoon that connects with the sea. The water is calm, almost no current at all, and crystal clear.
You can see fish and other fauna, birds feeding, etc. There are places where you can see sweet and salt water running together, the change of density is very noticeable, a beautiful thing to see.
The place is like a park, as if Disney had purchased and remodeled the lagoon. The borders and roads are well kept, with bronze and stone statues here and there. There are several benchs in which you can rest a while.
They offer locker service and rent snorkeling gear, they also charge an entry fee. The prices are on the pricey side for the average mexican, but I guess not so for the average 'merican.
Snorkeling is a must in this lagoon. You really won't be dissapointed. Watch out for the sea entry, the current is much stronger there, and while there is no real danger of going adrift, or drowning, it's important to notice. If you go there, make sure you're a good swimmer, you could end up in Akumal Beach, or in Villa Italiano (not sure of the name) beach; Yal-ku is in the middle.
If you arrive on public transportation, be prepared to walk about 3km from where the 'vans' leave you. You can walk on the street, watching the beautiful houses, or down the beach and then returning to the streets.
Akumal is mostly a foreign (USA) retirement colony, almost all the houses are owned by foreign people, and almost all of the hotels down the beach are all-inclusive plans from USA and Europe, expensive for mexicans. More so, some won't even offer services, food, etc, to you if you aren't a guest already.
The restaurants at the beachfront are also expensive, a lot, for the average mexican.
The way we did it was to come in the public, inexpensive vans that you take on Playa del Carmen, walk the 3km to the lagoon, hydrate with our backpacks, swim until tired, eat a little lunch we carried and stored with our things in the provided lockers, and walk back to Akumal beach. Then tour the beach, hotels and restaurants in the area. Finally, return to Playa del Carmen via the aforementioned vans.
All in all, a very good place to visit in family.
My rating doesn't go to excellent because of the high prices, and the fact that it doesn't feel like a virgin lagoon, it's too tampered with, beautiful as it is, but there are places that don't have that 'artificial' feel to them.
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