An interactive timeline describing the history and major events on the U.S./Mexico border (1519-1998) is available on the PBS website: www.pbs.org/kpbs/theborder/history/interactive-timeline.html
Check out this graphic animation of the morphing US/Mexican border:
www.pbs.org/kpbs/theborder/history/index.html, click on ‘morphing map’ at page bottom
To learn more about the U.S./Mexico border, its history, and current debates over it, see the list of related links compiled by PBS here: www.pbs.org/kpbs/theborder/history/index.html
For border history post-1998, check out the Humane Borders website, at: www.humaneborders.org/news/news4.html. Humane Borders, an organization committed to building a humane and just border environment, has compiled several detailed maps showing migrant deaths, rescue beacons, and water stations along the U.S./Mexico border from 2000-2007.