What are a couple of good ideas to celebrate a spring birthday for an adult?

There are many ways to celebrate a birthday for an adult in the spring. One could host a BBQ, either at home or at a park with BBQ pits. Another idea would be to have a picnic in a local park. If weather doesn't permit an outside activity, meeting with friends for brunch or dinner is another nice way to celebrate a birthday. For an activity that doesn't involve other people, treating oneself to a massage or spa treatment is another way to celebrate a birthday.