Emerald Pool, Lake in Mariposa County, United States

Emerald Pool is a small lake in Mariposa County, United States, set along a mountain stream. The water collects in a rocky basin, and a short trail leads to its edge, where the surface shows shades of green and blue.

The pool formed naturally where the stream slows over a ledge of hard rock. Over time, seasonal floods have shaped the basin and smoothed the surrounding stones.

People often stop here to cool off and take photos, and you might see families resting on the flat rocks. The name comes from the green tint of the water, which shifts with the light and the season.

The path to the water is short but uneven, with roots and stones underfoot, so sturdy shoes help. The flow is strongest in spring, and the rocks can be slippery, so watch your step near the edge.

The water stays cold even on hot days because it comes from snowmelt higher up. Look for small fish holding still in the deeper part of the pool, almost invisible against the green bottom.