Birds Nest Reserve, beside Yitshar, is a karstic, bell-shaped pit, 120 meters deep. The opening is about 15 meters wide, while the bottom is a cavern 40 meters wide. The shaft and the pit formed through the unique combination of three types of rock formations in the Shekhem (Nablus) region: the opening of the shaft is in a chalk layer that does not dissolve in water, while the inside is limestone, which dissolved over the centuries, creating the deep pit. At a certain stage, apparently about 80 years ago, the roof collapsed inward, and the cavern’s chimney was suddenly exposed.
Hundreds of different birds live in the shaft: pigeon’s, jackdaws (a type of raven) and cave sparrows. The official name of this nature reserve is Kamin Hasif, and it is protected by the Israel Nature and Parks Authority.
The best time to visit is in the late afternoon, so that when you look down (carefully!) you can see all the birds returning toward evening, folding their wings as they swoop down into the depths of the shaft and seem to free-fall until they reach the ledge where they nest.