At 4 km in length, it's one of the most important gorges of the Psiloritis range, and of central Crete in general. Rich in fauna and flora, it starts at the village of Zaros to the south of Heraklion and through the E4 path leads to the lush forest of Rouvas. The route is about 2.5 to 3 hours, and you can go hiking, bouldering and climbing. It takes its name from the chapel of Agios (St.) Nikolaos, which dates from the Byzantine period. There are two recommended routes: The first begins from the lake of Zaros and ends at Agios Ioannis. It is about a 2.5 hour hike, through a magical landscape with green surroundings and running water. The second is approximately twice as long, about a 5 hour hike. Beginning at Psarofarango, located on the plateau of Nida and through an easy, marked trail passes by Agios Ioannis and ends at Lake Zaros.