If you like to walk and you like plants, this is the place to go.
I myself am not a big walker or plant lover, so it did not hold the interest for me it did for my mother in law. She was visiting from Indiana and felt sheer joy during the time in the Arboretum.
There are so many different types of plants and a nice reprieve during the summer months when its hot. Lots and lots of shade and a nice breeze.
Best of all, it's free.
For the nature lover with good endurance, a nice place to take a walk