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The church of Hagia Sophia (literally "Holy Wisdom") in Constantinople, now Istanbul, was first dedicated in 360 by Emperor Constantius, son of the city's founder, Emperor Constantine. Hagia Sophia served as the cathedra, or bishop's seat, of the city. Originally called Megale Ekklesia (Great Church), the name Hagia Sophia came into use around 430. The first church structure was destroyed during riots in 404; the second church, built and dedicated in 415 by Emperor Theodosius II, burned down during the Nika revolt of 532, which caused vast destruction and death throughout the city.

"For 273 years, the little stone bridge that carries Frankford Ave. across Pennypack Creek has been doing its humble job with a minimum of attention..." 
 - Gerald McKelvey, The Philadelphia Inquirer, September 16, 1970

Colvin Run Mill is an early 19th century operating gristmill, closely modeled on the principles developed by Oliver Evans (1755-1819). Powered by a waterwheel, the restored mill was probably built on or after 1811 on the site of an older mill. Originally, the site was the property of George Washington, who identified it as ideal for a mill site. The first verifiable documentation of gristmill business was made by Philip Carter, who purchased a 90-acre property about 1811 from William Sheppard, who probably built the original mill based on Evans' design.