Marine scientists have discovered an exceptionally well-preserved terrestrial landscape submerged in the coastal waters of the Maltese Islands, which reveals how the archipelago would have looked like 20,000 years ago.

At this time, Europe was experiencing the last ice age and sea level in the Mediterranean Sea was 130 metres lower than at present.

Malta, Gozo and Comino were connected and the archipelago was two and a half times larger than it is today.

Dingli Cliffs towered 380m above sea level whilst Valletta was located 10km inshore.

The coastline from Marsalforn to Pembroke consisted of steep coastal cliffs that were incised by more than 20 valleys.

Numerous limestone plateaus hosted collapsed caves and featured landslides along their margins.

A 40 km wide land bridge connected southeast Malta all the way to the south of Sicily.

Sea level rise during the last 20,000 years has sunk 450 km2 of this landscape, meaning that the largest part of the Maltese Islands is today under water.

By surveying the seafloor around the Maltese Islands with state-of-the-art mapping technology, an international team of geologists has reconstructed the majority of this submerged landscape in great detail.

The results are going to be published in ‘Marine Geology’, a leading international journal reporting on developments in marine geology and geophysics.

They are important for a number of reasons. Several parts of this submerged landscape, such as caves and valleys, could have provided ideal sites for preserving evidence of prehistoric human occupation or animal activity. Further investigations may shed light on the origin of the Maltese megalithic society and animal migration routes to sites such as Ghar Dalam.

Moreover, submerged landscapes also comprise archives of past changes in climate and sea level, and their study will be crucial for predicting future climate change and its impact on the Maltese Islands.

The study also identifies which areas of the Maltese coastal waters constitute a hazard to seafloor infrastructure, deserve protection from human activities, or provide attractions to divers, thus contributing valuable information to marine spatial planners.

This study was led by Aaron Micallef from the University of Malta and forms part of Mapscape, a project involving CNR-ISMAR, National Oceanography Centre, CNR-IRPI and University of Modena and Reggio Emilia.