On this day: July 1

Published On: Jun 28 2013 03:06:05 PM CDT   Updated On: Jul 01 2014 01:00:00 AM CDT
Sony Walkman cassette player

The Battle of Gettysburg begins, America's first zoo opens, the first Tour de France starts, the Sony Walkman hits the market, the PG-13 movie rating is introduced, and the Deepwater Horizon oil spill breaks an unfortunate record, all on this day.