Tambaque is a clear spring and swimming spot north of Aquismon, usually visited on the same loop as the Mantetzulel caves. The water rises at the foot of the hills and collects in shallow pools surrounded by vegetation, making it a welcome cool-off after a cave walk.
It is a simple local place rather than a resort. Bring swimwear, a towel, and cash for community fees or food, and avoid sunscreen in the water unless it is reef-safe and biodegradable.