This collection of United States maps includes a year-by-year. Beginning from the Declaration of Independence and extending to present-day, students will learn explore and interact with these maps that change year-by-year.

A map of North America in 1840 at the time when the concept of "Manifest Destiny" was being applied to annex the Oregon Territory, Texas, and much of northern Mexico into the United States. The map is color-coded to show the extent of...