Historic silver mine shaft in Banská Štiavnica with a surviving baroque pump engine house, part of the UNESCO World Heritage Site.
Žigmund šachta is one of the historic precious-metal mine shafts of Banská Štiavnica in central Slovakia, whose mining district was designated a UNESCO World Heritage Site in 1993. The shaft was first sunk around 1631 at an altitude of 583.28 metres, with an earlier attempt abandoned after two years because of extreme rock conditions at depth. It was connected to the Svätotrojičná dedičná štôlňa (Holy Trinity drainage adit) during the seventeenth century.
The shaft was progressively deepened and by 1836 had reached its final depth of 359.715 metres, connecting to the drainage adit of Emperor Joseph II. In 1759 the engineer Jozef Karol Hell installed two water-column pumping engines at the shaft, each capable of lifting 494 cubic metres of mine water per day. In 1865 a steam pump by J. Sigla of Vienna replaced earlier arrangements.
The baroque pump engine house of 1759 survives at the shaft site and is a listed Národná kultúrna pamiatka (National Cultural Monument), declared in 1970.
Žigmund šachta forms part of the historic silver and gold mining complex of Banská Štiavnica, a town whose documented mining activity reaches back to 1156. Banská Štiavnica gained the status of a royal town in 1238 and by the eighteenth century was one of the most significant mining centres in the Kingdom of Hungary.
The shaft known as Žigmund was first sunk in 1631 at an altitude of 583.28 metres above sea level. An earlier attempt at the same location was abandoned after two years when the timber lining proved unable to withstand extreme ground pressures and hydrothermal alteration, which had caused the shaft casing to deviate from the vertical. When very hard rock was encountered at depth, a new shaft was begun approximately 40 metres higher in 1633, at the elevation that survives as the present shaft. During the seventeenth century the shaft was connected underground to the Svätotrojičná dedičná štôlňa (Holy Trinity drainage adit). A decision was subsequently taken to deepen the shaft further to reach the level of the Ján ore vein.
In 1759 the engineer Jozef Karol Hell installed two water-column pumping engines (vodostĺpcové čerpacie stroje) at the shaft. These machines drew on water supplied from the Klinger reservoir via a channel that is still partly visible behind the engine house building. Each machine was capable of lifting 494 cubic metres of mine water per day to the level of the Svätotrojičná dedičná štôlňa, a lift of 137.76 metres. A horse-operated pump served as a reserve during periods when water supply for the column engines was insufficient. The installation represented a significant technological advance and was part of a wider programme of water-column engine construction in the Banská Štiavnica district during the second half of the eighteenth century.
From 1826 the shaft underwent its final deepening, with the objective of reaching the level of the drainage adit of Emperor Joseph II. This work was completed in 1836, when the shaft attained its definitive depth of 359.715 metres. A period of increased pumping demand arose when part of the Emperor Franz drainage adit between Žigmund šachta and the neighbouring Amália shaft became flooded. To address this, a new steam pump manufactured by J. Sigla of Vienna was installed in 1865, with the pumps themselves supplied by the ironworks at Hronec.
Mining activity at the shaft declined in the second half of the nineteenth century as the richest ore zones were exhausted and the economic conditions of the district deteriorated. The shaft eventually ceased active extraction, though the surviving surface complex remained intact.
The baroque pump engine house building of 1759 stands at the shaft mouth on the street Na Žigmund šachtu in the Mestská pamiatková rezervácia (Urban Conservation Area) of Banská Štiavnica. It is a single-storey structure with a cellar, rectangular in plan. It was declared a Národná kultúrna pamiatka (National Cultural Monument) in 1970. The shaft waste heap is also recorded as a surviving feature of the site. The strojovňa (engine house) of Žigmund šachta was relocated to the Banské múzeum v prírode (Open-Air Mining Museum) at the Ondrej shaft site, which was opened to visitors in 1974 and has since received more than 1.3 million visitors.
The site forms part of the Banská Štiavnica and Technical Monuments of its Surroundings UNESCO World Heritage Site, inscribed on 11 December 1993. The complex of mining operational buildings at Žigmund šachta is listed as one of the significant components of the heritage district.