The first courtyard of the Castle is separated from the Hradčanské Square by the monumental Rococo bar fence, which consists of eight ornate columns and a gateway; the gateway is called the Gate of the Giants. The gate was designed in 1769 by the architect, Fratišek Platzer. The original courtyard was established during the reign of Rudolf II., but only the beautiful Matthias Gate that leads to the second courtyard was preserved. The gate was ordered by Rudolf II. but it was finished during the reign of his brother, Matthias, in 1614. Even the Latin inscription on the gate says that, “Mr. Mathias elected Roman Emperor, always noble Hungarian and Czech King. . . had built in 1641.” In terms of style the gate is a combination of the Rudolfine Mannerism and the Baroque. It is one of the first secular Baroque structures in Bohemia and it is said that the gate was designed by Giovanni Maria Filippi.
The buildings surrounding the first courtyard were established during the reconstruction of the Castle, during the reign of Mary Teresa. During that time, the architect, Nicolo Pacassi, had filled in the trench that was in front of the Matthias Gate. The trench was there since the first establishment of the Castle and the Armoury and Treasury were torn down in order to make room for the first courtyard. The freestanding Matthias Gate was incorporated into the new so-called Classical-Baroque Teresian wings of the Castle. The first courtyard served as the so-called Court of Honour. It is the place for honorary parades of the Castle Guard and also, in various political times it was where various official state visits were held and will still be held in the future.