We construct the kinematic associahedron motivated by quantum field theory. We then construct a compactification for M_{0,n}^{+} motivated by string theory and realize it as a curvy associahedron (worldsheet associahedron) and a positive geometry. Finally, we introduce stringy integrals, which on some limit determines the kinematic associahedron and its canonical function, and on another limit gives a diffeomorphism between the interior of the kinematic associahedron and the worldsheet associahedron, thus relating their canonical functions and canonical forms.