Schlossplatz Karlsruhe, Central square at Karlsruhe, Germany.

Schlossplatz Karlsruhe is the square south of Karlsruhe Palace, laid out as a baroque garden at the city's founding. Its central axis, the Via Triumphalis, forms the main ray of the city's fan of nine streets. The south side is closed by Weinbrenner's uniform Zirkelbauten, rebuilt after World War II with arcades facing the square.

The square was created in 1715 when Margrave Charles III William founded Karlsruhe as the new capital of Baden-Durlach. The palace was built as the center point and the city's streets were planned outward in a geometric pattern.

The square hosted Karlsruhe's fairs until the last Karlsruher Mess was held there in 1872. The Via Triumphalis, the central axis running from the palace through the square, forms the main ray of the city's fan of nine streets. The Zirkelbauten, a uniform row of buildings designed by Friedrich Weinbrenner, closes the south side.

The square lies south of the palace, bounded by the Bundesverfassungsgericht and the Botanischer Garten to the west and the economics faculty of the Karlsruhe Institute of Technology to the east, with the Kunsthalle to the southwest. The Via Triumphalis runs through its central axis toward the Marktplatz. A car park and a road underpass were built at its southern edge for the 1967 Bundesgartenschau.

The square's central axis forms the Via Triumphalis, the middle of nine streets that fan out southward from the palace. The southern edge is closed by the Zirkelbauten, a uniform row designed by Friedrich Weinbrenner; after wartime damage they were rebuilt as government offices with his arcades restored.