PBS
Nh Pbs: Nature Works: Estuaries
Learn more about estuaries when you visit this informative site. This resource provides locations of and weblinks to estuaries in the United States.
Curated OER
Etc: Maps Etc: Mexico and Western North America, 1845
A map of Mexico in 1845, prior to the ceding of the northern territories to the United States in 1846. The map shows the territories of Oregon, Texas, and Central America under Mexican control, and the frontiers of the Missouri and...
Curated OER
Educational Technology Clearinghouse: Maps Etc: The United States, 1850
A map of the United States in 1850, showing the frontier line, indicate by the thick black line. The map shows the States added to the Union between 1840 and 1850, including Florida (1845), Texas (1845), Iowa (1846), Wisconsin (1848),...