Pittsburgh boasts three rivers (the Allegheny, Monongahela and Ohio), nearly 450 bridges and one of the oldest documented structures west of the Allegheny Mountains (the Fort Pitt Block House)—and as of this fall, it plays host to HGTV's Restored by the Fords and DIY Network's Vintage Rehab. Tour some of the sites and sights that have made history in and around the 'Burgh with us!