The interior is in a state almost unchanged for two centuries. The chamber was created in the 1760s as a result of exploitation of a deposit from the Mysiur crosspiece. It took its name from the miner Krzysztof Mysiur; dimensions 7 m x 6 m x 2 m (length, width, height).

It was intended for horses working the ważyński horse engine, used in mines until 1963.

Pay attention to the ceiling of the excavation chamber that is supported by four hewn-wood cases using dovetail joints. There is a manger at the western side and above the stable is a chamber for storing fertiliser.

Horses worked in the Bochnia salt mine since its first centuries of existence. Initially, they only worked on the surface. They were used for auxiliary work related to mining and extraction, e.g., for transporting wood (extracting salt from mine waters required large amounts of wood!).

Even with the development of technology and the advent of devices for vertical transport, horses continued to be used inside the mines.

Horses working underground were treated with particular care. They were given dry and comfortable stables. Special safe transport tracts known as 'horse roads' were built between the increasingly numerous levels. Appropriate nutritional standards were defined and maintained, e.g., establishing a double amount of feed for the horses working below compared to those on the surface. As early as the 18th century they were provided with consistent care from a doctor and several blacksmiths.

The horses here were generally in good health. Interestingly, the very good results of the specialised tests of the condition of their airways, conducted in the early 1950s, were the impetus for further analysis and the beginning of climatotherapy in salt excavation areas.