The National Hamburger Festival is August 8th -9th, at Lock 3 in downtown Akron.
Saturday, August 8, 2015 12PM – 11PM
Sunday, August 9, 2015 12PM – 7PM
If you are interested in the semi-official history (please remember that anything you read on the web is subject to verification!) of the hamburger sandwich, here's a link to the Wikipedia page on the subject:
For complete information on the National Hamburger Festival, you can't do better than the organizer's own home page with links to everything from the schedule to participating restaurants:
Hope you have fun!