The restoration of Independence Hall at Independence National Historical Park was one of the most challenging projects ever undertaken there. A team of historians, architects, archeologists, carpenters, and painters carried out work that established historic preservation standards still used today. Their efforts revealed important details, including authentic paint colors and the originality of much of the woodwork, and made possible an accurate restoration of the building's interior. Workers installed paneling in the Assembly Room using 18th century methods, and while the work continued, the building remained open as much as possible to visitors. Historical architects Penelope Batcheler and Lee Nelson led much of the work, and Batcheler was considered tops in the otherwise male-dominated field.