The document summarizes some of the key physical features and cities of the Northeast United States. It mentions major lakes, rivers, and mountains like the Finger Lakes, Niagara Falls and Erie Canal, Mount Washington, and Mount Katahdin. Major cities highlighted include New York, Boston, and Philadelphia. The region has historically relied on resources like coal and fishing, as well as transportation along rivers, which led to the growth of factories, ports, dense population centers, and the establishment of a megalopolis in the Northeast.