Algonac is situated on what is called "the largest fresh-water delta in the world", at the mouth of the St. Clair River. Many canals wind their way throughout the city, which has given Algonac its nickname of "The Venice of Michigan." Mark Twain traveled through this area Wednesday, July 17th, 1895. Major Pond, in his journal wrote: "New Venice, on the St. Clair River, is a most interesting resort. I have seen nothing else like it in America.

Bad Wimpfen is a historic spa town in the district of Heilbronn in the Baden-Württemberg region of southern Germany. It lies north of the city of Heilbronn, on the river Neckar. https://en.wikipedia.org/wiki/Bad_Wimpfen

Baiae (in modern Italian Baia), a frazione of the comune of Bacoli in the Campania region of Italy, was a Roman seaside resort on the Bay of Naples. It was said to have been named after Baius, who was supposedly buried there. Baiae was for several hundred years a fashionable resort, especially towards the end of the Roman Republic. Baiae was even more popular than Pompeii, Herculaneum, and Capri with the super-rich, notorious for the hedonistic temptations on offer, and for rumours of scandal and corruption.

The state-approved health resort Seebach is located in the northern Black Forest in the upper Achertal . The Acher rises on the district of Seebach. The municipality extends from 400 meters up to the summit of Hornisgrinde in 1164 meters above sea ​​level . More than 75 percent of the municipal area is covered with forest. In the area of ​​the municipality of Seebach, directly on the Black Forest High Road, lies the Mummelsee at more than one thousand meters altitude.

Ouchy is a port and a popular lakeside resort south of the centre of Lausanne in Switzerland, at the edge of Lake Geneva (French: lac Léman).
https://en.wikipedia.org/wiki/Ouchy

Argentière is located near the head of the Valley of Chamonix approximately 7 km (4 mi) from Chamonix town. It is connected by road with Switzerland by the pass over the Col des Montets and the Col de la Forclaz to Martigny in the Rhône Valley.

See     SLC to Jane Lampton Clemens and Family, 26 Aug 1867., Yalta, Russia (UCCL 00145), n. 1. 

Mariánské Lázně (Czech pronunciation: [ˈmarɪjaːnskɛː ˈlaːzɲɛ]; German: Marienbad) is a spa town in the Karlovy Vary Region of the Czech Republic. It has a population of about 13,000. The town, surrounded by green mountains, is a mosaic of parks and noble houses. Most of its buildings come from the town's Golden Era in the second half of the 19th century, when many celebrities and top European rulers came to enjoy the curative carbon dioxide springs.

Archaeology has shown continuous occupation of the site of Bad Tölz since the retreat of the glaciers at the end of the Ice Age. For example, there are finds from the Hallstatt culture as well as from Roman Raetia, or at least occupation by romanized Celts.

Franzenbad, Kaiserhaus Hotel.

Františkovy Lázně  German: Franzensbad) is a spa town in Cheb District in the Karlovy Vary Region of the Czech Republic. It has about 5,500 inhabitants. Together with neighbouring Karlovy Vary and Mariánské Lázně, it is part of the renowned West Bohemian Spa Triangle.

At the beginning of the 17th century, the Aix people and the medical world had begun to become aware of the value of the hot springs of Aix, through the writings of the dauphinois physician Jean Baptiste Cabias, who was followed in this area by other renowned doctors. Indeed, since ancient times the exploitation of sources of hot water had never been completely forgotten. Bathing took place in Aix in the Middle Ages and until the end of the 18th century, in the only existing Roman pool, outdoors, or at home where the spa water was brought by hand.

Twain and Joe Twichell visited Chamonix in September of 1878 to view Mont Blanc, a 30 mile long massif along the French, Swiss and Italian borders.  A Tramp Abroad contains a burlesque account of an attempt to climb the mountain.  The tale is based upon Twain's watching a climb through a telescope and an account of 11 climbers who fell to their deaths in 1870.