For any set A of n points in ², we define a (3n - 3)-dimensional simple polyhedron whose face poset is isomorphic to the poset of non-crossing marked graphs with vertex set A, where a marked graph is defined as a geometric graph together with a subset of its vertices. The poset of non-crossing graphs on A appears as the complement of the star of a face in that polyhedron. The polyhedron has a unique maximal bounded face, of dimension 2n_i + n - 3 where n_i is the number of points of A in the interior of conv (A). The vertices of this polytope are all the pseudo-triangulations of A, and the edges are flips of two types: the traditional diagonal flips (in pseudo-triangulations) and the removal or insertion of a single edge. As a by-product of our construction we prove that all pseudo-triangulations are infinitesimally rigid graphs.