Kryštof (Christopher) adit and Mauritius mine

This adit which was uncovered again in 2008 and opened to the public in 2015 gives excellent evidence of different mining methods used from the late 16th to the late 18th centuries. The first meters of the adit walls are lined with dry masonry. The following section with perfect trapezoidal cross-sections was driven by means of a chisel and a hammer around 1590. At a distance of 80 m from the entrance, the adit circumvents the Mauritius shaft which was sunk later, in the 1760s. The crosscuts which appear in the section behind the shaft show clear indications of fracturing the rock by the method of fire-setting which was used in Hřebečná until 1743. The younger rear part of the adit is wider and higher and was driven already with the use of gunpowder for blasting the rock; in one place, the year 1778 has been engraved. After 262 m, the adit leads into a huge stope that is 65 m long, 4-9 m wide and 15-25 m high. The stope was first formed in the 16th century but enlarged in the 18th century.

The Kryštof adit is part of the Mauritius mine which was the biggest and deepest (220 m) tin mine in the Czech Ore Mountains. The deeper parts of the mine below the level of the Kryštof adit are currently accessible only by using speleological techniques, down to a depth of 15-30 m above the level of the main Blasius drainage adit (i.e. to a depth of ca. 100 m below the surface); below this point, the mine is inundated. The non-inundated underground of the mine is formed by a system of horizontal tunnels, vertical shafts and huge stopes which stretch across several original adit levels. The largest chamber of the system, unique in size not only in the Ore Mountains, was formed in the northern part of the deposit. The non-inundated part of this chamber is 60 m long, 40 m high and 15 m wide, however, it may be assumed that it originally reached the deepest parts of the mine. The preserved fragments of older parts of the mine often have a very regular oval cross-section, typical for fire-setting. The mine workings include a large number of dry walls as well as areas with carved niches for attaching the timberwork and support structures of the water draining machinery.