As of 2019, where is the only hotel in the world made entirely of salt?

Palacio de Sal or "Palace of salt" is a hotel built of salt blocks. It is located at the edge of 'Salar de Uyuni', the world's largest salt flat.

'Salar de Uyuni' is the world's largest salt flat at 10,582 km2 (4,086 sq mi). It is located in the 'Potosí' and 'Oruro' departments in southwest Bolivia, near the crest of the Andes at an altitude of 3,656 meters (11,995 feet).

'Salar de Uyuni' has long attracted tourists, who came great distances and needed a place to rest before returning to their cities. Building such a resting place required construction materials, which are scarce in the area. Therefore, it was logical to erect a hotel made of salt, which is in ready supply at 'Salar de Uyuni'.

The first hotel was built in 1993-1995 out of salt blocks in the middle of the 'Salar de Uyuni', and soon became a popular tourist destination. Its location in the center of a desert produced sanitary problems. The hotel had to be dismantled in 2002.

Around 2007, a new hotel was built, under the name Palacio de Sal. The new site is south of Bolivia's capital La Paz. The building was constructed of about 1 million 35-cm (14-inch) salt blocks, which are used for the floor, walls, ceiling and furniture, including beds, tables, chairs and sculptures.

The sanitary system has been restructured to comply with the government regulations. The hotel has a dry sauna and a steam room, a saltwater pool and whirlpool baths.