Travelers to Hillsdale Lake should stop at the visitor center at the northeast end of the dam. Many interpretive displays explain the lake's history, recreational opportunities, and natural resources. (If you are planning to visit the western parts of the lake, be sure to pick up a map because the roads can be confusing.) Behind the center, bird feeders attract resident sparrows, juncos, woodpeckers, and chickadees. The 1.5-mile Hidden Spring Nature Trail, which begins at the visitor center, takes hikers through an oak-hickory forest. Look for fox squirrels, white-tailed deer, woodland birds, and a couple of the most respected reptiles in eastern Kansas: the venomous timber rattlesnake and the copperhead. Flocks of ducks, geese, pelicans, and gulls are seen on the lake during migrations. Late November may bring large flocks of snow geese. At the bridge over Little Bull Creek, scan the flooded timber for wintering bald eagles. Throughout the year, look for cormorants, gulls, grebes, and ducks. A great blue heron nesting colony is visible to the west from the Rock Creek bridge. With binoculars and a spotting scope, approximately 50 large stick nests can be seen in the tallest sycamores growing from the creek bottom about 0.5 miles away. Both equestrians and hikers can enjoy the 24 mile horse trail east of the lake. (Caution: This is in a hunting area, so wear bright colors during hunting seasons).