The first patent concerning land in what was to become Tredyffrin was in 1681. There were no land purchases in the 1690s, 1720s, or 1770s. The reason for the moratorium in the 1690s is not clear, but there were problems in the 1680s with overlapping patents that may have been highlighted by Thomas Holmes’s map of 1687. The two main decades of land acquisition in Tredyffrin were the 1680s and 1700s. After the 1750s only a section of the North Valley Hills was vacant land.