The strange desert lakes and valleys of Ubar in Libya

The Ubari Lakes lie in Libya's far southwest Sahara. More than twenty bright blue pools sit in the sand and surprise visitors who expect only dunes. Long-ago earth shifts, wind blown sand and crumbling rock scooped out hollows that now hold the water. Rain that runs off nearby rock plus underground seeps and rare storms, feeds the lakes. The water carries so much salt that it tastes five times saltier than the open sea.

The whole sandy area covers about 7,000 square kilometres. The best known pools - Gabron, Um al-Maa, Mandara besides Mavo - share linked basins. After heavy rain the lakes grow - under the hot sun they shrink. Some fill only in winter or spring. As water leaves through evaporation, salt stays behind and the salinity rises. Tiny salt tolerant algae turn a few pools blood red.

Under the sand lie water bearing rock layers but also hard sheets that block flow. This hidden plumbing keeps life alive. Ducks and herons pause here on long flights across the Sahara. In the saltiest water live small fish found nowhere else on earth.

Tuareg herders call the lakes sacred. Stories passed by word of mouth praise the water as both gift and spirit place. Old camel trails once linked the pools - traders used them as natural stops on journeys across the sand.

Today the lakes dry faster as droughts grow longer. Wells dug nearby pull water away as well as conflict blocks guards from watching the area. News of the danger spreads and local people, officials and help groups now work together to fence off fragile shores or limit new wells. Libyan families return to walk the dunes, watch birds and rest in the shade of the valleys. The quiet water reminds them that life still holds its place in the Libyan desert.