The ability to measure land surface topography over large areas to assess natural hazard threats posed by seismic and flooding events is a critical, international need. Interferometric synthetic aperture radar (INSAR) has been used to map topography; however, accuracies are limited because observations are not measurements of true surface topography over vegetated areas. Instead, the measurements, which depend on the sensor and the vegetation, represent some height above the true surface.We develop a two-step correction for the INSAR imagery to account for penetration into the vegetation. The INSAR imagery is first adaptively filtered to reduce random measurement noise. We then combine the INSAR with polarimetric radar and laser altimetry data to account for the vegetation contribution to the topographic heights.