The Pont-Neuf viaduct located on the Gouessant valley in the communes of Hillion and Morieux by the engineer Harel de la Noë from 1912 is considered one of the most impressive testimonies of the genius of its designer and its sense of aesthetics indisputable.
The work was part of the 2nd railway network on the line Yffiniac/ Matignon opened in the entirety of its route on June 27, 1926 and closed on December 31, 1948.
Rehabilitated in 2014 by the General Council, it has now found a new utility by allowing the passage of the Véloroute and the many hikers and walkers.

Patrimoine ferroviaire, des transports et du génie civil