Bacunayagua Bridge, Concrete bridge over Yumuri Valley, Cuba.

The Bacunayagua Bridge is a concrete structure that rises roughly 110 meters above the Yumuri Valley, connecting the provinces of Mayabeque and Matanzas. The bridge spans about 313 meters across a deep canyon with a substantial central section that demonstrates significant engineering.

Construction began in 1956 under engineer Luis Sáenz Duplace, with the project by the firm SACMAG and execution led by Sáenz Duplace and Manolo Arvesu. The bridge was inaugurated on 26 September 1959 in the presence of Fidel Castro and Celia Sánchez, and opened to traffic on 3 October 1959. It was built using prefabricated segments and, for the first time in Cuba, semi-arches based on Josef Melan's system.

The bridge is one of the seven wonders of Cuban civil engineering, a status often repeated by Cubans who cross the Via Blanca. Its 1959 inauguration drew Fidel Castro and Celia Sánchez, and the roadway opened to traffic on 3 October 1959. From 1976 to 2010 the span marked the provincial limit between Havana and Matanzas, and since 2011 between Mayabeque and Matanzas.

The western side of the bridge has a stopping area where visitors can step out and view the valley below. This spot works well for a brief pause during travel to appreciate the surroundings.

The 114 m figure is the arch span, not the deck length: the total crossing measures over 313.5 m. The steel arch was assembled in two halves and rotated into position, using the Melan system of semi-arches, applied for the first time in Cuba.