The Lakes Region Conservation Trust manages this trail. In their "Red Hill Trail Map", available at their headquarters in Center Harbor, they describe the Sheridan Woods Trail as follows:
This trail runs from the trailheads on Sheridan Rd to high ground on southeastern Red Hill, with views of Sandwich Dome and Mt Israel at the highest point. Grade - moderat, though most elevation is gained fairly early on; distance - 2.5 mi. (The distance must be wrong...it is shorter than this to the viewpoint.)
So, enjoy your hike and geocaching experience.