Garden Tower is a high-rise building in the Innenstadt district of Frankfurt, Germany. It was built between 1973 and 1976 as the headquarters of Landesbank Hessen-Thüringen and was one of the first high-rise buildings in Frankfurt's financial district, the Bankenviertel. The building, designed by architecture firm Novotny Mähner Assoziierte, was commonly referreā¦Garden Tower is a high-rise building in the Innenstadt district of Frankfurt, Germany. It was built between 1973 and 1976 as the headquarters of Landesbank Hessen-Thüringen and was one of the first high-rise buildings in Frankfurt's financial district, the Bankenviertel. The building, designed by architecture firm Novotny Mähner Assoziierte, was commonly referred to as Helaba-Hochhaus until Helaba moved to a new location, the 200-metres-high Main Tower, in 1999. The tower underwent a major renovation from 2003 to 2005 and was reopened under its current name.