Sharing lot space with the historic Central Washington Agricultural Museum, Fullbright Park is one of several parks managed by the City of Union Gap that is available for reservation. However, the trails here are available to the public if the park isn't reserved for an event, and the short one mile loop is a nice add-on to a visit to the museum.
The park has a network of unofficial trails, but marked signs lead you in a loop about one mile long. Hike uphill, gaining about 500 feet in half a mile. It's very steep and can be slick when wet. No switchbacks here!
Near the top, the signs lead you across a small gully to the next hill, and then you go downhill just as steeply as you ascended. The trail spits you out on a gravel road inside the agricultural museum (open to pedestrian traffic year-round). Exploring the museum is a fun closure to this short-but-sweet hike.