Geology of the Blue Trail at Thacher Park at 2:00 p.m. The blue trail in the southern portion of the park is a hidden gem and doesn’t necessarily get explored too often. Along this trail, you’ll pass a series of cliffs and some fields full of grikes. Wear appropriate footwear for walking on and off trail to view the geology. Meet at the Paint Mine parking lot. Pre-register for this program by calling the park office at 518-872-1237. Park entrance fee is $6 per vehicle.