It's pretty cool being the same age as your town-- in fact, almost exactly! I do believe the official founding date of Columbia is June 1, 1967; I was born a scant six weeks later, on July 17.
But this year Columbia is celebrating its birthday on June 23rd, which of course is today! CA has what would seem would be a great day of activities planned at the lakefront, which can be found here.
It should be another awesome weather day today, so get out there and wish Columbia a happy 45th! You never know; an unscheduled Marshmallow Man personal appearance may just break out!