To the south, the Zeughaus’ main façade crowned with trophies opens with an elaborately ornamented main entrance onto the boulevard Unter den Linden. The ornamentation honours the Kingdom of Prussia, founded in 1701, and the military glory gained by the Brandenburg-Prussian army.
The medallion portrait of Friedrich I is in the central niche above the double doors. He ruled as Elector of Brandenburg from 1688 and as King in Prussia from 1701 to 1713. The laurel-wreathed gilded bust was placed over the main entrance in 1706. To the left is the Brandenburg eagle; and to the right, the Jupiter eagle holding a bundle of lightning. Above it, flanked by the Roman deities Fame and Victory (Fama and Viktoria), is the coronated Prussian royal coat of arms. This is surrounded by the Order of the Black Eagle, established in 1701 — the highest order of chivalry in the Kingdom of Prussia.
Above it is a Latin inscription in gilt letters which sets the programme for the Zeughaus’ sculpture. It translates as: “To pay tribute to the deeds of arms, to terrify his enemies, to protect his friends and allies, Friedrich I, the exalted father of the Fatherland, sublime and undefeated King of Prussia, had this armoury built from the ground up in 1706, for the storage of all weapons of war as well as wartime spoils and trophies.” However, construction work inside the Zeughaus wasn’t completed until several years later — in 1730, in the reign of King Friedrich Wilhelm I.
The pediment above the inscription shows a mythological scene. The goddess Minerva receiving weapons and armour from the hands of bearded blacksmiths led by the god Vulcan. She is arming herself for battle. This is a reference to the Zeughaus itself, where weapons, such as cannons, muskets, sabres and ammunition, were stored for use in the event of war.