KORBOUS, Feb. 4 -- With a Mediterranean coastline, natural thermal springs, clement weather and affordability, Tunisia has become the world's second-largest destination for seawater-based treatments known as thalassotherapy.

Now, it is setting its sights on overtaking France to claim the top spot.

"The main advantage of Tunisia is its coast and thalassotherapy," compared with neighbouring countries, said Mario Paolo, an Italian, at the Korbous thermal spa, perched on a hill an hour's drive from the capital, Tunis.

A 78-year-old retiree who has lived in Tunisia for the past five years, Paolo said he frequently visits Tunisian thalassotherapy centres "to get back in shape".

"Enjoying sea water and natural springs is not just leisure but...