This paper describes an interactive system for creating geometric models from many uncalibrated images of architectural scenes. In this context, we must solve the structure from motion problem given only few and noisy feature correspondences in non-sequential views. By exploiting the strong constraints obtained by modelling a map as a single affine view of the scene, we are able to compute all 3D points and camera positions simultaneously as the solution of a set of linear equations. Reconstruction is achieved without making restrictive assumptions about the scene (such as that reference points or planes are visible in all views). We have implemented a practical interactive system, which has been used to make large-scale models of a variety of architectural scenes. We present quantitative and qualitative results obtained by this system.