At Tzoumerka, where the water and the rivers are abundant, the visitor gets the chance to visit and traverse many stone bridges. These edifices, beside their practical use, constitute the ultimate feat of architecture and elegance, since they fit in perfectly in the surrounding environment. The most famous among them is that of Plaka, which was constructed in 1866. Its dimensions (61 m. of length and 20 m. of height) make it the largest one-arch stone bridge in the Balkans. It was the border between Greece and Turkey for over 30 years.