On Highway 29 -- Drive north to Calistoga. As you apporach Calistoga, you will come to a blinking traffic light. Highway 29 becomes Foothill Blvd. (Rte. 128) at that point. Go straight: We are 4 blocks north, on the left. From Highway 101 -- Take the Mark West Springs exit (4 miles north of Santa Rosa), go east following the signs to Calistoga. Turn left on Petrified Forest Road (you must turn either left or right), again following the Calistoga sign. Petrified Forest Road ends at Rte. 128 (Foothill Blvd.). Turn right: We are about 1 mile down on the right.