The Powel House Museum and Garden is one of the most architecturally significant buildings in the city, and the country. This Georgian style mansion, built in 1765 can be found in many art history textbooks. Home to Samuel Powel, the "Patriot Mayor", who was the last mayor of Philadelphia under the British crown, and the first under the new republic, the house is a restored peek into the life of the wealthy and powerful during the time of the American revolution. All the Founding Fathers visited and dined here, and you can too. it takes a about 40 minutes to do the tour, and it's definitely worth the trip (they're only open Thurs-Sun in the afternoons).