North of Santa Fe, the New Mexico landscape is framed by four high mountains. Although they are sacred to the Tewa Pueblo Indians, the four peaks are in different bureaucratic and cultural zones, which means that each peak attracts visitors but few non-Indian travelers visit more than one of the mountains. Tom Harmer’s chronicle of climbing all four of these mountains in one summer—Sandia to the south, Chicoma to the west, Canjilon to the north, and Truchas to the east—offers a unique view of a montane forest unlike any in the world, where mountain, plain, and desert biota converge. Outdoor enthusiasts and armchair travelers alike will relish Harmer’s precise account of his backpacking adventure, in which this sixty-two-year-old Anglo discovers the realities of complicated cultural legacies, ecological challenges, and human foibles counterpoised against his own strengths and frailties.