Bimmah Sinkhole | Sur

Bimmah Sinkhole, locally known as Hawiyat Najm (The Falling Star), is a water-filled depression located in the Muscat Governorate, within the borders of the Hawiyat Najm Park. It is one of the most visited natural landmarks in Oman, situated between the coastal towns of Dibab and Bimmah.

Visual Characteristics

The sinkhole is a symmetrical limestone bowl approximately 50 meters by 70 meters wide and 20 meters deep. The water at the bottom transitions from a vibrant emerald green to a deep turquoise, depending on the depth and sunlight. The surrounding limestone walls feature dramatic overhangs and vertical layering. A concrete staircase provides stabilized pedestrian access from the rim to the water level.

Location & Access Logistics

The site is situated approximately 125km southeast of Muscat and 75km north of Sur.

Transit: Fully accessible via the Muscat-Sur highway (Route 17).

Vehicle Requirement: 2WD is sufficient for all access roads and the paved parking area.

Entry: The sinkhole is located within a fenced public park. Entry is free, and the gates typically open from 08:00 to 20:00.

Historical & Geological Origin

While local legend suggests the hole was created by a meteorite (hence the name Hawiyat Najm), geologists confirm it is a solution sinkhole. It was formed by the collapse of a limestone surface layer due to the dissolution of the underlying carbonate rocks by groundwater. The water at the bottom is a mix of fresh groundwater and seawater infiltrating through an underground tunnel from the Arabian Sea, located 600 meters away.

Key Highlights & Activities

Swimming: The brackish water is suitable for swimming. The depth increases significantly toward the center.

Natural "Fish Spa": The water contains small Garra rufa fish that nibble on the skin of submerged swimmers.

Cliff Jumping: Local youth frequently jump from the lower limestone ledges, though this is officially discouraged for safety reasons.

Park Facilities: The surrounding Hawiyat Najm Park offers landscaped walkways and shaded seating areas.

Infrastructure & Amenities

Facilities: Modern public restrooms and changing rooms are located near the park entrance.

Picnicking: Numerous shaded benches and green spaces are available within the park boundaries.

Connectivity: 4G and 5G cellular signals are consistently strong.

Safety: The perimeter is fenced, and the staircase is equipped with handrails.

Best Time to Visit

The winter months (October to April) offer the most temperate climate. To avoid large crowds, visit on weekdays or before 10:00 on weekends. For photography, midday provides the most direct sunlight into the sinkhole, illuminating the turquoise water to its maximum vibrancy.

Technical Details

The water level in the sinkhole fluctuates slightly with the ocean tides due to the subterranean connectivity. The salinity level is lower than the open sea but higher than pure freshwater. The temperature of the water remains relatively constant year-round, typically between 25°C and 28°C.

Nearby Landmarks

Fins Beach (White Beach) – 12km South

Wadi Al Arbaeen – 30km North-West

Wadi Shab – 33km South

Wadi Tiwi – 35km South

Quriyat – 50km North-West