Hamilton Hollow to Green's Cave
1.9 miles one way to Meramec River, 2.4 miles one way to Green's Cave.
This hike, which is not described in most guidebooks, follows Hamilton Creek from the trailhead to the confluence with the Meramec River and can be extended to visit Green's Cave half a mile down river. The entire hike is within Meramec State Park. The trail is not maintained. In some parts you may have to find your path among different faint traces or walk off-trail. There are several creek crossings on rocks or logs. The hike is best done in winter to avoid ticks.
Direction to trailhead:
Take 185 to the State Park, past the Visitor Center and across the bridge over the Meramec. Immediately after the bridge, turn right onto Sleepy Hollow Road (brown sign to Hamilton Hollow Trailhead). After 1.5 miles, keep right onto Hamilton Hollow Road. The pavement ends after another 0.5 mile. Continue 2.1 miles further on good gravel road to trailhead parking lot on the right.
The trailhead is at the site of the former Hamilton Ironworks. A 0.2 mile long interpretive trail leads to the remnants.
After exploring the ironworks, head towards the creek. Cross the creek and start hiking on the right side of the creek (looking downstream). After 0.5 mi, cross the creek again to the left side. A valley opens from the left, and the trail enters an old overgrown pasture. At the end of the pasture, 0.6 mi from the trailhead, a track towards the left leads to Hamilton Cave. Take a few minutes for a detour and look at the cave entrance.
Shortly after returning to the path, cross the creek again. At 0.8 mi, Pratt's Spring is on the left.
After another creek crossing, you reach the site of an old homestead at 1.5 miles. Here the trail is less pronounced, with several faint traces crisscrossing the overgrown pasture. A small creek emerges from Homestead Spring, and you can see the ruin of the spring house.
Cross Hamilton Creek again to the right side, and continue to the confluence with the Meramec River at 1.9 miles.
Right across from where Hamilton Creek meets the Meramec begins a large island that extends downriver. Green's Cave is in the bluffs on the right side of the river, located approximately across from the island's end, 0.5 mile downstream. Follow a narrow path near the river to Green's Cave. With a cave entrance 28 m tall and 33 m wide, Green's Cave is considered the cave with the largest cave entrance west of the Mississippi (http://www.showcaves.com/english/usa/caves/Greens.html).
A little below the cave, a trail leads to the top of the bluff.