Castle square is the place where the main attractions of the Greenhouse. The main tourist attraction, which gave its name to this square, is a majestic castle, built on the site of an ancient convent. He appeared in the XVI century by order of the wolf Rusovici. From the monastery buildings have been preserved dungeons and a small chapel. Nowadays, the castle turned into a Museum. His collection of archaeological finds, paintings, porcelain and coins comprise more than 2 million copies.

The centre of the Castle square is adorned with the Marian column, which is crowned by a sculpture depicting the Holy Trinity. It was established in 1718 as a thank you for ridding the Greenhouse from the plague and for the salvation from the terrible disease four brothers clari-Aldringen who owned the local castle. Column created in the Baroque style and is considered one of the best works of the sculptor matyáš Braun.

To the castle Greenhouse adjoins the Church of the exaltation of the Holy cross, which was built in 1549-1568, in the Renaissance style and later rebuilt in the Baroque manner. At the moment, the Church belongs to the Orthodox Church.

Another temple facade overlooking Castle square, dedicated to the name of St. John the Baptist. On the temple grounds are buried many members of the count's family clari-Aldringen.

On the North side of the square you can see three-storey house which is informally called the "Golden Cross". It was built on the site of an old Teplitsky school. The building in the Empire style appeared in 1809, when his owner purchased two plots of land, including the place on which stood a dilapidated school, do not be restored. In this mansion met the monarchs of the allied forces before the decisive battle with the forces of Napoleon at Leipzig.