I didn't end up having a wild party for my 40th, rather, I stayed at a hotel and had two friends come over. We went to dinner, had snacks, and watched our baseball home team in the playoffs get into the World Series.
On my birthday, I went to our local aquarium which gives birthday people free passes. I also met up with some more friends and had dinner at an Italian restaurant instead.
As for wild parties that year, I went to the big city celebrations because our home team had just won the World Series. I grew up with two of them and so that was a big birthday present.