Millstones testify to the importance of milling in Lancaster County. The first mill was built only a few years after the Mennonites arrived in 1710, and because mills were vital to agriculture, their number grew to over 200 by 1839. Most were gristmills where grain was processed, but other mills crushed hemp for rope or obtained tannic acid from bark. Millstones also ground cocoa for chocolate, pigments for paint, and apples for cider. During the 18th and 19th centuries, mills were central to life in Lancaster County, and towns often grew from these gathering places. Today few of these mills still operate, and even fewer continue to use millstones. Early milling techniques using such stones can be seen at Millbridge Village on the Pequea Creek, where the mill was begun in 1738 by John Herr, a grandson of Hans Herr.