Conceived in 1977, the Rephotographic Survey project was an effort to locate and rephotograph the sites of the government survey photographs of the late-nineteenth century. The entire project, 120 pairs of images, is presented here along with an essay by chief photographer Mark Klett on the methodology and problems encountered with rephotography and an evaluation by critic Paul Berger of the issues raised by rephotography. This is a remarkable look at the influence of time on nature.