 Otto Rehnig – the architect responsible for the similarly fated Hotel Esplanade Berlin – was commissioned to design a hotel to accommodate the floods of passengers arriving in at the Anhalter Bahnhof across the street.When the Excelsior first opened on 2 April 1908 after over two years of construction work it accommodated a modest 200 rooms but when an additional section was built on Anhalter Strasse 6 in 1912/13 the hotel had already almost doubled in size.The untimely re-opening of the hotel on the eve of World War I meant that the building spent its early existence comparatively empty.