The bottom of the Argentine Central Railroad Grade begins at a closed gate that keeps vehicles off. There are many offshoot trails on the climb up, but the trail is clearly marked with signs.
You'll pass by a few old mining sites along the way and most likely will hear the train whistle of the Georgetown loop railroad. Climb for 3.0 miles until you reach Pavilion Point. At Pavilion Point, you'll see the remnants of an old chimney. There are also some fantastic views of Silver Plume and the Georgetown loop railroad.
From Pavilion Point, the road now becomes a doubletrack jeep trail. Continue down the road 0.8 miles until you run into the Leavenworth Creek Road. The ACRG will continue for many more miles up the steady road to reach McClellan Mountain. Rideers looking for a shorter and easier loop could turn left and ride down to the pavement to complete a counter-clockwise loop through Georgetown and back to the parking area.
Otherwise, keep following the Argentine Central Railroad Grade all the way up the 4x4 road.