The Commons Knowledge project, supported in part by the Sprout Fund, is an innovative way for park users to engage with park features and trees. Take a stroll through Allegheny Commons and explore; while in the park scan the QR codes that appear at the map locations above to see historic images, watch videos and listen to audio stories about the park. A QR code is a new type of barcode that can be scanned by downloading a free QR code reader on your Smartphone through the App Store.