America’s development as a young nation was shaped by scientific, geographic, and cultural explorations like the Corps of Discovery Expedition led by Meriwether Lewis and William Clark (1803–1806), which was charged by President Thomas Jefferson to find a westward route to the Pacific Ocean and document the plants and animals encountered along the way. These and other expeditions helped build an early understanding of the nation’s remarkable biodiversity and diverse ecosystems. More than two centuries later, those landscapes continue to evolve. Wildlife populations have responded to changing land use, human settlement, conservation efforts, and environmental conditions. We invite you to join us as we resurvey the expedition’s trail using wildlife cameras to document modern biodiversity and explore how America’s wildlife and landscapes have changed over time. We have geotagged and mapped historical wildlife observations from the expedition journals so they can be compared with wildlife documented by our modern resurvey. Cameras will collect images throughout the growing season (April–October) at locations extending roughly 80 km on each side of the trail, approximating the landscapes the expedition encountered. Our task is to identify the species captured in these images, count the animals present, and record visible behaviors and characteristics. Together, these observations will allow us to compare where species were recorded by Lewis and Clark with where they occur today and where they may be found decades into the future. By connecting historical records with modern wildlife observations, you will help scientists understand how species distributions have changed over two centuries while building a lasting resource for future research on America's ecological history. In many ways, this project continues a tradition of discovery that began with the Corps of Discovery itself. While the tools have changed—from field journals to camera traps—the goal remains the same: documenting the living world and deepening our understanding of the wildlife that shares it with us.