sentences:  The design and engineering of the DMC Landmark Building was performed by Albert Speer Jr..The building was to house an observation deck on 104th floor at , from which visitors will be able to see the entire metropolis of Frankfurt and it would have been the 4th tallest building in Europe.It would have been an observation deck less high than those of Willis Tower on the 103rd floor at and the 102nd floor of the Empire State Building at .