Saudi Arabia’s blue holes: Geological wonders driving conservation and discovery

Dubai: Saudi Arabia’s Blue Holes — a chain of deep-sea sinkholes stretching along the southwestern coastline between Makkah and Jazan — are quickly gaining recognition as one of the Kingdom’s most remarkable natural features. These striking circular depressions, visible as dark blue pools against the Red Sea’s lighter turquoise waters, offer a rare glimpse into geological processes that have unfolded over millions of years.

Formed through rock fissures, limestone dissolution, tectonic shifts, and the gradual collapse of ancient underwater cave systems, the blue holes are considered invaluable geological archives. Their steep vertical walls and layered sediments allow scientists to study past climate patterns, sea-level changes, and long-term developments within the Red Sea basin. For researchers, each sinkhole is a natural time capsule preserving evidence of marine evolution.

What are blue holes?

Blue holes are deep, vertical underwater sinkholes found in carbonate rock formations around the world, including well-known examples in Belize, China, and even a modest one in the UAE. They form unique ecosystems rich in biodiversity and serve as havens for sea turtles, reef fish, marine mammals, invertebrates, and specialised organisms that thrive in low-light, low-oxygen environments. Their depth and isolation often result in distinct water chemistry, creating conditions that are unlike those of the surrounding seas.

Recognising their ecological and scientific importance, Saudi Arabia designated the Blue Holes Protected Area, now one of the Kingdom’s largest marine conservation zones. Spanning more than 16,500 square kilometres and including over 20 islands, the protected area shelters coral reefs, migratory species, and sensitive coastal habitats vital to Red Sea biodiversity.

This conservation effort aligns with Saudi Arabia’s Vision 2030 goals, which prioritise expanding protected natural areas, enhancing sustainability, and fostering responsible eco-tourism. By safeguarding these underwater formations, the Kingdom aims to support scientific research while opening opportunities for nature-based tourism and community engagement.

Silent, ancient, and visually captivating, Saudi Arabia’s blue holes remain among the Red Sea’s most incredible natural wonders — still holding secrets waiting to be uncovered.

 With inputs from SPA