Mount Gibraltar Trachyte Quarries Complex, also known as the Bowral quarries and The Gib is a heritage-listed former stone quarry on Mount Gibraltar at Oxley Drive, Bowral, Wingecarribee Shire, New South Wales, Australia. It was worked from 1886 to 1986, providing stone blocks from the igneous rock (both trachyte and syenite) for significant public buildings, monuments, and other uses, both locally and further afield, including overseas. The complex was listed on the New South Wales State Heritage Register on 2 December 2013.

Quarrying commenced in the Mount Gibraltar area following the opening of the railway in 1867. William Chaker commenced operations at the site in 1885 at the top of Cliff Street when he opened the NSW Trachyte Stone Quarrying Company (Quarry D). The "Gibraltar Rock Quarries" were opened by Messrs Leggat and Company in 1886. John Leggat supplied the Bowral Trachyte piers for the Hawkesbury River railway bridge, his last major project before going broke, still the largest scale use of the stone.

By 1888 Loveridge and Hudson, who had been quarrying poorer quality stone at Quarry A at the top of Oxley Street, took over Chaker's quarry. Notable builders of the period, they had blocks quarried for buildings such as the Equitable Life Building (George Street, Sydney) the Australasia Bank (corner of Martin Place, Sydney) and the anchor blocks for the Hampden Bridge in Kangaroo Valley.

By 1890 the Pope family was quarrying blocks (Quarry C leased from John Thompson) of which the largest was 9 tons 7 hundredweight; these became part of a gate pillar for Centennial Park (Sydney). The blocks were often taken out by rail from a specially constructed siding in Bowral. The quarries also provided local building stone and several quarries provided kerb stones and tramway supports for local towns as well as Sydney.

In 1881 the Amos Brothers acquired Quarry E on the western face of Mount Gibraltar, along Soma Avenue (Amos spelt backward). By 1888 they were producing stone for railway ballast. In 1890 the government resumed part of their land and opened the Government Ballast Quarry (Quarry F). This closed after 2 years and after a court case, Alexander Amos got back the land that had been resumed.

The NSW Government quarry on the Mittagong side supplied rock to a crusher via a double light rail system. There were a great many quarrymen and stonemasons working at the time, some living in poor circumstances in temporary dwellings on top of the mountain. There were many accidents and the men formed the "Berrima District Workmen's Accident Relief and Endowment Fund" as a result.

As early as 1894 the government geologist E. F. Pittman urged the use of Bowral Trachyte "for any important building in which permanence might be desired. The "trachyte" may, for all practical purposes, be regarded as indestructible". When Edwards Raht chose the Bowral material for 350 George Street (Equitable Building) he compared it to Cologne Cathedral saying it would last for not a hundred years but a thousand.

In 1906, geologist and later Antarctic explorer Douglas Mawson published a paper about the geology of the area, in particular the aegirine in the syenite igneous rocks. This remained the only scientific study of the minerals in the rocks until a University of Wollongong honours student wrote a paper about the pegmatite veins in the rocks in 2004.