Documenting patterns of land use and land-cover change in mountain resort development (MRD) is important for understanding the effects of these changes of fragile mountain environments. High-spatial-resolution imagery can be useful for mapping MRD, but lack of a long-term record of such imagery hampers our ability to analyze temporal patterns. We use the results from classification of high-spatial-resolution imagery (Quickbird and LiDAR) to calibrate concurrent moderate-resolution imagery (Landsat). We then use historical moderate-resolution imagery to analyze changes in spatial patterns of MRD over time. Analyses revealed that increases in MRD occurred disproportionately close to streams, which raises concerns for impacts on water quality.