John Muir city park is located along I-41 in Green Bay. You can walk to the fence and watch the highway (it's LOUD). There is also a lot of open grass and a nice playground. Bring your own pen! Good luck!
John Muir also known as "John of the Mountains" and "Father of the National Parks", was an influential Scottish-American naturalist, author, environmental philosopher, botanist, zoologist, glaciologist, and early advocate for the preservation of wilderness in the United States of America.
