An accessory mounting system suitable for mounting a plurality of accessories at a windshield portion within the interior cabin of a vehicle comprises a housing that is adapted for releasable mounting to a receiving structure on the interior surface of the windshield of the vehicle. The housing houses at least two accessories, at least one of which is selected from the group consisting of a forwardly-viewing camera and a forwardly-viewing rain sensor. Another of the at least two accessories is selected from the group consisting of: a) a vehicle altitude sensor, b) a vehicle incline sensor, c) a headlamp sensor, d) a daylight sensor, e) a geographic positioning satellite (GPS) transmitter, f) a geographic positioning satellite (GPS) receiver, g) an antenna, h) a camera, i) a microphone, j) a compass sensor, k) a rain sensor and l) a photosensor. The at least one of the two accessories housed by the housing views through the windshield of the vehicle when the housing is mounted to the receiving structure on the windshield.