The Detroit Riverwalk is a long path along the Detroit Riverfront. Strung along the path are parks and landmarks with lots of fun outside things to do.
Hines Drive is a 17 mile long stretch of road that follows the Rouge River from Dearborn to Northville. The land is essentially one really long, skinny park. There is a bike trail along the entire length of the road. There are also many playgrounds, a disc golf course, dog park and an RC car track.
Belle Isle is a large island in the Detroit River. Essentially a large park. There is a road that circles the island. With several fountains, buildings, statues and landmarks to explore Belle Isle is a nice way to spend a couple of hours or an afternoon. There is also a kids play area.
Eastern Market is one of the areas largest local food markets. On Saturdays (and Tuesdays from July - October) hundreds of open air stalls are open to the public from 7am to 4pm. Located between Gratiot, Crysler Freeway and Mack Ave in the City of Detroit.
Pewabic Pottery, located at the corner of Jefferson Ave and Cadillac Ave in Detroit, is the world famous manufacturer of ceramics, specifically ceramic tiles. There is a free self-guided tour (with guidebook from the website) through the National Historic building which houses a museum, fabrication studio and tile showroom.