The Prussian eagle had its wings right from the start: When the demolition work began on the north wing of Frankfurt Central Station on January 12, 1972, the first thing that was broken out of the facade was a sandstone block weighing more than three tons with the Prussian heraldic animal.

It was noted that dismantling began at exactly 10:38 a.m.

The northern part of the magnificent terminus station, opened in 1888, with its long-distance tracks had to make way for the underground future of local public transport in the region in 1972. A huge construction pit would be excavated at this point in the following months: 56 meters wide, 75 meters long and 22 meters deep, an excavation volume of around 71,000 cubic meters of earth. In the pit, space was to be created for a station of the new S-Bahn on the lowest level, above that a subway station and finally an underground shopping arcade, the B-level.

The work in Frankfurt had little in common with a classic demolition: Instead of driving up heavy equipment, the approach was very sensitive so that the reconstruction of the listed station building would succeed. "Every cuboid and every cornice is numbered with meticulous precision, photographed and stored in a place in Groß-Auheim so that it is ready for rebuilding," noted FAZ author Herbert Seemüller on January 13, 1972.

Three weeks later the next visit to the construction site, now things got rougher: “Suspended ceilings weighing several tonnes patter down five or ten meters on the ground.

Dust whirls up, covers everything in clouds.

Compressed air drills roar, engines run.

If you risk a look behind the centimeter-thick, dusty scaffolding tarpaulin from the platform, you will think you have been transported back to the post-war period.

Meter-high rubble piles up, splintered beams lie around. ”Less than a generation after the end of the Second World War, the association with the destruction after a bombing was obvious for many viewers.

Heavy equipment was not used that much.

Two crawler excavators and a mobile crane did most of the work.

Six small trucks that were able to maneuver on the platform helped with the dismantling and removal of the rear facade to the tracks.

The decision in favor of the elaborate open construction method was not without an alternative when planning since the late 1960s. It would have been possible to excavate the structure under the main train station by means of mining. With this tunneling method, a significant part of the City Tunnel, which went into operation in several steps from 1978, was finally realized, which today extends from the main train station via Taunusanlage, Hauptwache, Konstablerwache and Ostendstraße under the Main to the local train station. Meanwhile, all lines of the S-Bahn Rhein-Main with the exception of the S7 run through the tunnel. In the other direction, the new S-Bahn station under the main station was connected to the station apron via short tunnels and three ramps, two single-track and one double-track.The ramps come to light at the level of the S-Bahn workshop, the former post station.

In fact, the project went smoothly

A meticulous financial calculation by the Bundesbahn preceded the choice of the construction method: Including the demolition and reconstruction of the north wing, the project was to cost 75 million marks in the open construction process.

If the cavern were to be excavated by miners, however, at least 85 to 90 million marks were expected.

The prospect of savings of up to 20 percent in construction costs was the decisive factor.

In fact, the project went smoothly - unlike comparable metropolitan transport projects a century earlier.

During the construction of the first London Underground with the “cut and cover” method in June 1862, the main sewer “Fleet Sewer” broke and put the construction site three meters deep under sewage.