The spectacular Vikos Gorge in northwest Greece, topped by massive rounded cliff buttresses and craggy walls in light grey and orange-yellow, is classified by the Guinness Book of Record as the world’s deepest, plummeting some 3,000 feet, a gold based on both depth and width-to-depth ratio.

The gorge is found in the core zone of the Vikos–Aoös National Park, in the Zagori region. It begins between the villages of Monodendri and Koukouli and ends near the village of Vikos (or Vitsiko). The gorge collects the waters of a number of small rivers and leads them into the Voidomatis River which forms in the gorge. The major part of Voidomatis is only seasonal, and is permanent only at the lowest part of the gorge. Vikos is also a site of major scientific interest, because it is in almost virgin condition, it is a haven for endangered species and contains many and varied ecosystems.

The landscape of the 20 km long gorge, 12 km οf which belongs to the park’s core zone, presents a diverse relief and is characterized by abrupt altitudinal changes. Steep slopes and precipitous rocky cliffs dominate in the middle and higher zones respectively. Numerous gullies dissect both sides of the gorge and the movement of water detaching various rocky materials creates extended screes. The gorge, with a northwest-southeast direction, has been carved over millions of years by the Voidomatis River, a tributary of the Aoos. The Voidomatis, is mostly seasonal, with year-round flow occurring only in the lower part of the gorge. As the Vikos Gorge is a deep cross section, its slopes expose a series of rocks of different age. The upper layers consist of limestone formations, while the lower ones of grey dolomite. A special feature of the limestone, resulting from its chemical weathering to water, is its carstic nature. Since limestone dissolves as the water percolates through its pores, an extended underground drainage system is developed with caves and channels that enlarge with the time when their roofs collapse producing rocky exposures and perpendicular slopes. For the same reason the water is scarce, and only when an impenetrable stratum is met, the water appears on the surface.

There is a natural viewing platform over the deepest part of the gorge at Oxia, a location 3 km by a newly-constructed road from the village of Monodendri. Another viewpoint over the gorge is at Beloi, on the eastern side of the gorge, accessible from the village of Vradeto.

A hiking trail descends into the gorge from Monodendri. The trail then leads north through the gorge to the springs of the Voidomatis river, from where paths lead out of the gorge to the village of Papingo on the north side of the gorge, or to the village of Vikos on the south side of the gorge. It is also possible to hike south through the gorge from Monodendri to the 18th century stone bridges near Kipi.