Sand box or Climber???
Well ... we had a swing set, which dd used as a climber and it was so wobbly that we took it down and trashed it. She rarely used the swings but used the pole that held the swings as a monkey bar to go across the set. Then when her friends would come over and swing, the adults had to hold it down because the kids would make it airborne. Scared me to death! I was glad to see it go.
That left her with the sandbox. Even at 5, she still loves it and is in it often. In fact, I have a table of plates and cups filled with sand from her latest tea party!
Wish we had a solid climber though. The wood kind that would support the "monkey" in her. She needs an activity that she can take some of that incredible energy of hers out on. But they are just too expensive.