1. In 1813, the Battle of Delaware Bay took place during the War of 1812. British warships attempted to invade the state but were repelled by American forces.

2. The Delaware Memorial Bridge, which spans the Delaware River and connects Delaware to New Jersey, was officially opened on May 11, 1951. It is one of the largest twin suspension bridges in the world.

3. On May 11, 1957, the DuPont Company introduced Teflon, a non-stick synthetic material, to the public. Teflon has a wide range of uses, from cooking pans to medical equipment.

4. In 2013, Delaware became the 11th state to legalize same-sex marriage. Governor Jack Markell signed the bill into law on May 11 of that year.

5. May 11, 1985, was declared "Jack A. Markell Day" by then-governor Michael N. Castle. Markell, who would go on to become governor himself, was recognized for his leadership and service to the state of Delaware.

These are just a few of the significant events that have taken place on May 11 in Delaware's rich history. From battles to bridges, scientific breakthroughs to political milestones, this date continues to hold a special place in the state's collective memory.