In the summer of 2015, a 6.5-mile extension of the white-blazed South Taconic Trail, constructed by volunteers, was opened. The southern trailhead is now on Shagroy Road, just north of Millerton, New York.
Heading north from Shagroy Road, the trail crosses a stream and skirts the edge of a small pond. At 0.2 mile, a red-blazed trail leads in 0.3 mile to the Rudd Pond Camping Area. The South Taconic Trail continues on a wide woods road, climbing gradually. At 1.5 miles, another red-blazed trail on the left heads downhill, reaching Rudd Drive (the park entrance road) in 0.6 mile. Here, the South Taconic Trail turns right and continues to ascend, passing, at 2.2 miles, a west-facing viewpoint that offers a broad vista of the Harlem Valley and beyond to the Catskill Mountains.
The trail crosses the private Kaye Road at 3.5 miles and continues to ascend, passing several more viewpoints, with the most spectacular viewpoint being the final one, at 6.2 miles. After descending steeply, the South Taconic Trail reaches a junction, at 6.5 miles, with the Quarry Hill Trail. This side trail leads steeply downhill over a rocky shoulder of the ridge, to a small parking area on Quarry Hill Road, 6.7 miles north of the center of Millerton.
The junction with the Quarry Hill Trail marks the northern end of the 2015 extension of the trail. The South Taconic Trail continues north, leading in 1.3 miles to the summit of Brace Mountain, in 1.6 miles to a junction with the red-blazed Mt. Frissell Trail, and 5.5 miles to the summit of Alander Mountain.