The 8th of June is World Oceans Day. A fitting moment to consider something that has been working quietly for centuries yet rarely gets discussed in the same breath: thalassotherapy and thermal mineral bathing.
Both use water as their medium. Both have a measurable effect on the body. The source differs, and so does what they do.

Thalassotherapy draws on everything the sea has to offer: seawater, algae, mud and sea sand. In a thalasso centre, these elements are applied through targeted treatments such as hydro circuits, seaweed wraps, Vichy showers and Jetstream therapy. Seawater is rich in minerals and trace elements that are absorbed through the skin. The effects: improved circulation, reduced muscle tension, calmer skin and deeper sleep. In serious thalasso hotels, a medical consultation on arrival is standard. The doctor uses it to draw up a personal treatment plan.

Thermal water is heated by geothermal processes deep within the earth's crust. As it rises to the surface, it absorbs minerals from the surrounding rock. Which minerals depends on the local geology, which is why no two springs behave the same way. Magnesium calms the nervous system and supports sleep. Sulphur helps with skin conditions and joint complaints. Calcium and sulphate support digestion. Bathing in thermal water stimulates circulation and relieves pressure on the joints. The treatment discipline is called balneotherapy. Specialist health resorts incorporate it into focused programmes, often under medical supervision.

Less than an hour from Valencia, a handsome 19th-century villa sits within easy walking distance of the Costa del Azahar coastline. Palasiet has been run by the same family for decades, quietly building a reputation as one of Spain's most consistent thalasso addresses. All cure programmes are medically supervised and cover the full range of thalassotherapy. Alongside the treatments, there is a full weekly schedule: yoga, cookery workshops and walks. The microclimate of the region, with the sea, the surrounding mountains and the scent of pine, is very much part of the experience.

Every programme at The View Bouznika is built entirely around the individual and managed under medical supervision. Moroccan traditions and contemporary treatment methods sit alongside each other in a setting that is wholly focused on renewal.The hotel stands on Morocco's Atlantic coast, just over an hour from Casablanca. The combination of Moroccan tradition and medical precision is what sets this place apart.

Right on the sea in the Algarve, with its own private beach. The indoor pools at the thalasso centre are filled directly with water from the Atlantic Ocean. Vilalara brings together one of Europe's most comprehensive thalasso offerings and five-star comfort. Six restaurants, five outdoor seawater pools, and a full activity programme including yoga, Pilates and sound healing. The resort sits entirely within a green coastal landscape. For those who want a focused cure without compromise.

Beneath a historic monastery in Castile and León, the Manantial de San Bernardo spring surfaces with water rich in sulphate, calcium and sodium, known for its beneficial effect on digestion, liver function and metabolism. Castilla Termal is also the place for those who want a proper thermal cure without the clinical atmosphere. There are no restrictions. Good food and a glass of wine are entirely at home here.

For more than forty years, Bad Nieuweschans has been one of the most established health resorts in the Netherlands. The mineral water is rich in magnesium and salt. The facilities are extensive: a large sauna area with various saunas and steam rooms, a beauty centre and several restaurants, all under one roof. Yoga weekends on fixed dates are bookable here, finishing with time in the mineral baths. Your room is a dressing-gown walk from the thermal pools. The most accessible option for a short reset close to home.

What sets Preidlhof apart? Three things: its own thermal spring with sulphite, fluoride, bromine, iodine and traces of lithium, well suited to skin complaints and muscle and joint problems. A four-storey sauna tower offering 5,500 m2 of saunas, thermal pools and rest areas. And a kitchen where healthy cooking and refined dining are not mutually exclusive: regional South Tyrolean dishes, farm to table. This adults-only hotel in the mountain landscape of South Tyrol brings together traditional Chinese medicine and homeopathy with a full daily programme of yoga, sound healing and fitness classes. The view shifts between snow-capped peaks and flowering apple orchards.
Thalassotherapy works particularly well for fatigue, stress-related complaints and skin problems, and for those who need the sea as an environment to genuinely switch off.
Thermal mineral bathing is more effective for joint and muscle complaints, digestive issues, and where specific minerals such as magnesium or sulphur are relevant. The setting here is continental or alpine rather than coastal.

This blog is written by Marleen, founder of PureandCure.com (established in 2005). She travels around the world in search of the best Health & Wellbeing Hotels, Spas and Retreats and shares her insights, experiences and observations through her blogs.