Original sentence: A third period of four mission foundings was started in 1748 with the establishment of  San Ignacio, or San Ignacio de Velasco as it is known today which was not declared a World Heritage site.The church is a faithful 20th century reconstruction of the original built in 1761
Edited sentence: A third period of mission foundations began in 1748 with the establishment of  San Ignacio, or San Ignacio de Velasco as it is known today, which was not declared part of the World Heritage Site.The church is a faithful 20th-century reconstruction of the original built in 1761