Length:	1 mile
	Access:	Greentree Trailhead Simpson Park Trailhead
	Surface:	Asphalt
	Terrain:	Level
	Uses:	Walking, biking and skating
	Hours:	7:00 a.m. – One half hour past sunset

From Big Bend Road in Kirkwood, Marshall Road descends downhill into the Meramec Valley. At the base of the hill is Greentree Park, and on the left, is the entrance to the Greentree Trailhead of the westbound Meramec Greenway Trail. A short distance along that trail there are restrooms and water.

A mile further west on Marshall Road, just past the bridge over Grand Glaize Creek, on the left is the entrance to the Simpson Park Trailhead. Near that trailhead is an intersection of the Meramec Greenway Trail and the Blue Heron Trail. The Blue Heron goes north, crossing Marshall Road, and passing through Simpson Park and along Simpson Lake. Restrooms and water are available here.

The distance between these trailheads is one mile. The City of Kirkwood manages Greentree Park and St. Louis County manages Simpson Park.

The Meramec Greenway Trail in Greentree Park passes through a park-like setting with such features as a river access, picnic areas and a radio-controlled model car track. In Simpson Park the trail passes through a bottomland forest with sycamore and silver maple trees most common. In the early twentieth century this entire area was filled with recreational structures.