Holden Arboretum, located in Kirtland, Ohio, is the nation's largest arboretum. It covers 3,600 acres, and contains 120,000 plants. There are beautiful display gardens, lakes, and hiking trails. Some of my favorites are the rhododendron garden, lilac garden, wildflower garden, and butterfly garden.
With twenty miles of trails, Holden Arboretum is a perfect place for hiking. If you enjoy bird watching, this is a great place for that, too.
The arboretum is open daily from 9:00 AM to 5:00 PM. Admission is $6.00 for adults and $3.00 for children.