The present invention discloses a method for producing a hydrogel with one or more channels or a network of channels, said channels having a diameter of 1 cm to 50 µm, wherein one or more longitudinal members or a network of longitudinal members of a first material, said first material having a solubility in water at 25°C of 5 to 500 g/l, is provided and a hydrogel of a second material is formed which hydrogel covers and includes the longitudinal members at least partially and wherein the longitudinal member(s) is (are) at least partially removed from the hydrogel in the course of the formation of the hydrogel to form a hydrogel with one or more channels or a network of channels.
