Part of my thesis project for the Archaeological Park of the Colosseum, was a location-based social network for users to observe memories of their own or other users left precisely at that location. This allowed one to leave a memory, or a trace, exactly at the place one was visiting. In the context of the Park, this system was intended to incentivize visitors from around the world to leave their own memory next to the world's most beautiful monuments, giving them an excuse to return in the future to experience them a second time. Again, this system allowed the Organization to be able to leave guides and videos precisely around the monuments. I designed graphically and developed the entire project. The biggest challenge? How can a digital element be anchored to the physical space? If I see a memory in front of me, and I do a 360 with my phone, what does the memory do to stay in exactly the same position? To solve this problem, and really develop the project, I had to use a real “anchor,” a QRCode. In fact, the user had to scan the code, and from there the app began to calculate the displacement and orientation of the device via gyroscope. In this way, without using GPS, elements in AR could be placed even in small, indoor environments.