In 1998 the City of Frankfurt approved a new high-rise development plan which specifies where new skyscrapers are allowed to be built in the city . One of the approved locations was the estate owned by Commerzbank and Rheinhyp at Taunustor , right at the heart of Frankfurt 's financial district . The development plan envisioned a high-rise building for the property , named Kaiserkarree . In 2000 architecture firm Gruber Kleine-Kraneburg won an architecture competition for the planned tower , but the project slowed down after the Dot-com bubble burst in 2000 and the September 11 attacks in 2001 . Meanwhile the Rheinhyp became part of real estate bank Eurohypo and moved to Eschborn , therefore Commerzbank took over responsibility for the property
September 11 attacks
September 11 attacks
Taunusturm