The oldest operating roller coaster in Spain is Montaña Suiza (Swiss Mountain), located at the Monte Igueldo Amusement Park in San Sebastián. Opened in 1928, this "scenic railway" style coaster was designed by German engineer Erich Heidrich and offers stunning views of the Bay of Biscay. Unlike modern coasters, it features a track made of concrete troughs with steel rails and requires an on-board brakeman to manually control the speed of the train as it traverses the terrain. It is officially recognized as the oldest steel-railed roller coaster still operating in the world. Its historic charm, combined with its unique location on a coastal cliffside, makes it a significant cultural landmark in San Sebastián, providing a rare "time-capsule" experience that has remained largely unchanged for nearly a century of continuous operation.