Over time as demand for brownstone grew, more quarries opened. The workforce consisted of immigrants from Europe. By 1871, the majority of the workers were Irish; later Swedish immigrants comprised the majority. Until the 1850s when steam-powered equipment was introduced, the work was carried out primarily by hand, with oxen and horses helping haul rock away. The quarries operated almost continuously until the 1920s (they were closed during WWI).
Demand for brownstone declined due to a number of factors including the emergence of concrete as a building material. It was also a victim of its own popularity; people simply began to want something different. Additionally, floods in 1936 and 1938 filled the quarries with water and despite efforts to pump the water out, they could not be drained. Quarrying did continue until 2012 but at a far smaller scale. The park opened to the public in 2007.