Happy San Jacinto Day!

Tomorrow, April 22, is the 170th anniversary of the Battle of San Jacinto in which Texas won its freedom from Mexico (and you thought it was just Earth Day).

In 18 short minutes, on April 21, 1836, General Sam Houston led his Texian soldiers to a decisive victory over the Mexican Army, officially securing Texas' independence from Mexico and leading to the addition of one million square miles to the United States.

As a result of that battle, Texas won the right to put up an ineffective border so that all the Mexicans could come back in 170 years later.