Two more new features now under construction at Historic Mill Creek Discovery Park near Mackinaw City are a 40-foot climbing wall and a 50-foot tower that will offer a view of the Straits of Mackinac and Mackinac Island. These elements have been added to other new natural history features currently under construction at the park, Mackinac State Historic Parks announced April 11.

The Nature Trail Climbing Wall will become the third experience in an "Adventure Tour" package, which will include a trek through the treetops on the new Forest Canopy Bridge and an aerial cable ride on the Eagle's Flight Zip Line. The tour costs $5 in addition to park admission.

The climbing wall, attached to the side of the 50-foot tower, will contain interactive panels that will include sounds and sights of forest creatures.

Set on the park's eastern bluff, the five-story Treetop Discovery Tower is now being constructed. At ground level, visitors can learn about the dynamic habitat between the forest floor and the top of the trees. At the top of the tower, they will find out about the recovery of the American bald eagle.

The Forest Canopy Bridge and Eagle's Flight Zip Line are nearly complete and set to open to the public May 5. A playground and a children's interactive display of 18th-century water wheel replicas are scheduled for completion before opening day.

Features that have long been in place at the park include an 18thcentury water-powered sawmill with demonstrations, a sawpit with demonstrations, a nature program, and 3.5 miles of nature trails.