Media Luna

Laguna de la Media Luna is a crescent of clear water fed by five artesian springs that push warm groundwater up from vents deep in the lagoon floor, holding the whole lake at around 27 degrees every day of the year. That combination - warmth, clarity and depth - made it a freshwater diving destination: certified divers descend to the vents where the sand boils gently and the visibility runs long, past submerged logs and, famously, the site's palaeontological reputation - mammoth and other Pleistocene remains have been recovered here, and archaeologists have found offerings, so diving is regulated and directed. Snorkelers and swimmers get the shallows and the channel where the outflow river leaves the lake; families camp under the ahuehuete trees, and the surrounding semi-desert makes the blue look impossible from the entrance road. Rules protect it: no sunscreen, no boats with motors, designated swim zones, and dive access only with authorized operators. Simple palapas, showers and camping keep the park practical rather than pretty.

What you actually see

• The spring vents - warm water welling from the lagoon floor.
• The clarity - visibility that makes divers look airborne.
• The crescent shape - the lagoon's namesake curve.
• The camp shade - ahuehuetes over the picnic ground.

When to go

Year-round thanks to the constant temperature; weekdays and mornings for the calmest, clearest water. Holiday weekends bring campers in force.

Honest expectations

Diving requires certification and an authorized operator - the archaeological protections are enforced. Sunscreen bans apply to everyone. Facilities are basic and the surrounding town is workaday.

Nearby

Rioverde's plaza and orange groves lie minutes away; the Huasteca's waterfalls begin two hours east.