The present invention relates to a method of generating an artificial blood vessel organoid, comprising providing stem cells capable of vascular differentiation, stimulating mesoderm differentiation in said stem cells, stimulating vascular differentiation in said stem cells, developing a cell aggregate from said stem cells, embedding said cell aggregates in a collagenous 3D matrix and stimulating vascular differentiation of the aggregate in said collagenous 3D matrix; organoids obtainable from said method, uses of said methods and organoids in manipulation and screening studied and kits for performing the methods.