In the Rosengarten, a 25 percent natural thermal brine bubbles up from a depth of 243 meters, one of the strongest in Central Europe, which was mentioned in documents as early as 1125. It is pumped from the heart of the old town directly into the Thermalsolbad. There it is used for various therapeutic purposes.

The Kniestedter Gutshaus dates back to 1533 and is probably the oldest half-timbered house standing in Salzgitter. The building was demolished beam by beam in 1975 at its old location, directly west of the Kniestedter Kreuz road structure, and rebuilt in 1976 at the Kurpark in Salzgitter-Bad. The relocation of the Kniestedter Gutshaus was the first step towards creating an island of tradition in the Warnestraße and Marienplatz area. Together with the adjoining Tilly House and the charming half-timbered buildings on Marienplatz, the old Kniestedter Gutshaus is a valuable addition that has created a historical core.

The Tilly House is named after the general Tilly. He took up quarters there during the Thirty Years' War in 1626 after the Battle of Lutter am Barenberge.