Crows typically build their nests in the crooks of tree branches near the trunk, in bushes, on the side of cliffs or in the nooks of man-made structures. They very rarely place their nests at ground level.
Crows are a monogamous bird species, with both mates cooperating in the building of the nest and the gathering of food. The nest is made from dried sticks and twigs with soft inner linings composed of animal hair, bark and pine needles. Crows have been known to insert shiny objects they have found into the construction of their nests. They only nest during the mating season; then they begin to roost in larger groups. These roosts grow as fall and winter approach and can reach sizes of up to 2 million birds.