This spa resort is located in Yverdon-les-Bains, one of the oldest cities in Switzerland. The sulphuric springs of Yverdon-les-Bains were already used by the Romans as a place of worship and probably to supply in water the nearby thermal baths built during the first century CE. During the 18th century, the city decided to rehabilitate and build new thermal installations. Some of these buildings are still visible today as they are now part of the Grand Hôtel des Bains. It is open all year round and offers a variety of services from pools, wellness centre, private spa, fitness facilities, to restoration and accomodation. © Wikimedia/ADnine