Le Locle is a municipality in the Canton of Neuchâtel in Switzerland.
It is situated in the Jura Mountains, a few kilometers from the city of La Chaux-de-Fonds.
It is the third smallest city in Switzerland.
Le Locle is known as a center of Swiss watchmaking, even cited as the birthplace of the industry, with roots dating back to the 1600s. The municipality has been home to manufactures such as Favre-Leuba, Mido, Zodiac, Tissot, Ulysse Nardin, Zenith, Montblanc, Certina as well as Universal Genève, before the latter company relocated to Geneva. The town's history in watchmaking is documented at one of the world's premier horological museums, the Musée d'Horlogerie du Locle, Monts Castle, located in a 19th-century country manor on a hill north of the city Restored historic underground mills can be seen in a cave located about one kilometer west of the city center.
The name of the town derives from the word for lake or trou d'eau.