Staying in the Main Wincopin Trail system via the main parking area it is about a 4.5 mile intermediate ride or add the Yellow and White Trails for an extra 2.0 Miles up and back of advanced stream crossings, log rolls, and rock gardens, all makable.
The recommended route from the Main Trail Head: There is some doubling back but it maximizes the distance while minimizing overlap in the same direction and makeability:
Start: Main Parking Lot->Stait on Red Trail, this is the main (wide) trail through the park)-> Left on Green Trail->The Green trail merges with the Blue Trail, stay on it all the way to down to almost river level (This portion of the trail is not on many maps)->Make a Left on to the Green Trail (The Middle Patuxent River is in front of you), make a hard Left and follow a wide section of trail that runs along the Little Patuxent River, past the ruins of an old bridge, make a hard Left and up a “long” hill-> Merge back with the Blue trail-> Make a Left and stay on the Blue trail (don’t go straight on the Green Trail), make a Left back on the Green trail and down some stairs (Line: Left on the first section, it turns Right and cross the stairs, then ride down the right of the stairs), make a left and ride along the Little Patuxent River->Make a Left on the Blue tail and back up the hill->Trail merges with the Green (Yes you have been here before)->Make a Left and stay on the Blue trail (don’t go straight on the Green Trail)->Make a Right (don’t go Left this time) and the trail merges with the Green trail->Make a Left on the Green trail (don't go straight on the Blue trail), cross a small bridge->Left on the Red trail->Quick Left again on the Red trail and go down the stairs, and ride along the Middle Patuxent River, this loops around, [Advanced option: Make hard Left on the Yellow this is a short loop and comes back around to almost the same spot. It has a quick drop and back up a rock garden. If you want more, follow the White trail along the Middle Patuxent under the I-95 for about a mile until you get to Vollmerhaussen Rd. almost at Murray Hill Rd. The Trail ends here and you have to go back the way you came. The White trail is by far the most challenging option with log rolls, stream crossings, and rock gardens…all makeable at times (Rains affect the trails). A mile up and a mile back.]-> Make a Left on the Red Trail, go straight at the next fork->Make a Right on the Green Trail->Left on the Blue trail->Right on the Red Trail->Back to the parking lot.