What is this event?

Dad had this labeled "Pioneer Day 1976" but since baby Mike is IN the pictures, and Mike was not born yet on Pioneer Day 1976, I'm saying DAD IS WRONG!

So what event is this, and where is it? I don't recognize that chapel. There are about a dozen pictures from this event, including one where Mike Hicks is holding baby Mike. But I'm hoping these two will be enough to jog the memory.