Maestranza de San Bernardo, Historical railway workshop site in San Bernardo, Chile.

The Maestranza de San Bernardo is a former railway workshop featuring multiple reinforced concrete buildings including a central workshop, blacksmith shop, boiler house, and roundhouse. The layout shows how work was organized to maintain and repair locomotives and train cars.

In 1913, under EFE director Alejandro Guzmán Schremser, a tender was called for a Central Railway Workshop, and 121 hectares of the Cerro Negro estate in San Bernardo were bought. The San Bernardo workshops were built between 1916 and 1921 and officially began operating in April 1920. They became South America's second-largest railway workshop, exporting axles and wheels and building at least six steam locomotives.

The date 6 October is now Chile's National Railway Workers' Day, established by Law 20581 in 2012 to honour eleven Maestranza workers detained and shot on Cerro Chena on 6 October 1973, weeks after the coup. The central pavilion, smithy, boilermaking shop, locomotive turntable and main gate were declared a National Monument in 2010.

The complex lies in San Bernardo, in the Metropolitan Region of Santiago. In 1995 most of its land was sold for housing, so the preserved buildings now sit among 1,800 houses and 800 apartments. The central pavilion, the smithy, the boilermaking shop, the locomotive turntable and the main gate were declared a National Monument in 2010.

The San Bernardo workshops could build a complete steam locomotive, not just repair one: at least six were produced there, and axles and wheels were exported to other countries. The 1923 brake and iron re-rolling shops included a reinforced concrete chimney. In 2010 the central assembly shop, the smithy, the boiler shop, the locomotive turntable and the main gate were declared a National Monument.