En (Ein) Avdat comes as a huge surprise in this otherwise bone-dry desert: a year-round, freshwater spring that miraculously flows over a waterfall and through a narrow, winding ravine with steep sides of soft white chalk. Caves along the trail were inhabited by monks during the Byzantine period. To protect habitat for fauna such as the ibex, swimming and wading are prohibited.
The park has two entrances. The northern one, Zinim (Tzinim) Cliff, is just outside Midreshet Ben-Gurion's big yellow gate, while the southern one – which offers panoramas but no trails down into the wadi – is on Rte 40, 4km north of the Nabataean ruins of Avdat National Park. Except in designated picnic areas, eating in the park is not allowed; the only toilet facilities are at the entrances and at the Lower Parking Lot.
The two most popular trails begin at the Lower Parking Lot, a 3km drive from the northern entrance. The Short Route (start at least 1½ hours before the park closes) is a 1.6km circuit that takes you to En Avdat pool and the waterfall and back. The one-way Long Route (start at least 2½ hours before the park closes) goes to the park's southern entrance; because one section involves ladders that you can climb but not descend, this route cannot be done in the other direction. From near the southern entrance, it's easy to catch buses going north or south. A longer trail (15km) leads to En Akev, a freshwater spring (swimming permitted) further down Wadi Zin; count on this route taking six to seven hours.
The best times to visit are in the spring and fall. Park staff can provide you with a map and details on hiking options.