It is possible to make interwoven structures by using two or more surfaces with holes. Several solutions are known. And also interwoven structures have been made with two or more 3D objects with holes. One example is M.C. Eschers Double Planetoid , a combination of two tetrahedra. In this paper I show that we dont need two or more separate surfaces: even with one single surface we can make interesting interwoven structures which seem to be multi-layered, in 2D as well as in 3D.