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Parking for lower trail (easiest access to Sector A). Look for a blue sign that says Manitou Mountain Trail. Note, however, that the lower trail is NOT the Manitou Mountain Trail. The Manitou Mountain Trail follows the top of the escarpment.
Parking for the upper trail / logging road (easiest access to the boulders and Sector B). Look for a blue sign that says Eagle's Nest Lookout.
Manitou Mountain Trail parking