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Hidden Earth Atlas
Geomorphic & geological oddities

Bimmah Sinkhole

هوية نجم

Muscat Governorate, Oman · 23°02′10″N 59°04′16″E

Turquoise water of the Bimmah Sinkhole seen from the rim
Photo: Wikimedia Commons contributor, CC BY 2.0, via Wikimedia Commons

A limestone sinkhole 600 m from the sea, filled with turquoise water where fresh and salt water meet, with steps down from a free municipal park.

The sinkhole formed when the roof of a cave in the coastal limestone collapsed, leaving a bowl 50 by 70 m across and about 20 m deep at the visible surface (divers report it continues much further). Seawater seeps through the rock and mixes with fresh groundwater, which produces the colour. Small fish nibble at swimmers' feet.

Local legend attributes the hole to a meteorite, hence the Arabic name, "the deep well of the falling star".

Why it stays quiet

It sits between Muscat and Sur and gets tour buses briefly around midday. Early morning or after 3 pm it is often empty, and it is free.

Where it is

23.03610, 59.07110 OpenStreetMap Google Maps

Before you go

Changing rooms and toilets in the park. Swim only in calm conditions. No shade at midday.

Updated 2026-09-06 · Suggest a correction

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