The La Chaux-de-Fonds–Les Ponts-de-Martel railway is a metre-gauge railway in the Swiss Jura. It is operated by the Transports publics Neuchâtelois and has connected the municipalities of Les Ponts-de-Martel and La Sagne in the Vallée des Ponts with La Chaux-de-Fonds since 26 July 1889.
A TRN railcar enters La Chaux-de-Fonds from the Vallée de la Sagne in 2011