The Black Canyon of the Gunnison National Park is one of the lesser known national parks out there, but it is worth a visit if you are in the area. The Black Canyon of the Gunnison is probably not a destination national park, like the Grand Canyon or Yellowstone, where seeing the park is worth a trip all by itself. The Black Canyon of the Gunnison is not a huge park, it has 1 visitors center and no food available.
What it does offer is some great views of a steep and narrow canyon. There is a drive that goes down the rim of the canyon with various stops where you can take short hikes down to some better viewpoints. Some of these are under 100 yards, some a several hundred yards. There are also a number of other trails that provide longer trails, most of those are about 2 miles roundtrip.
The closest city to the Black Canyon of the Gunnison is Montrose, Colorado (not Gunnison, as you might guess from the name).