If you're coming from south of Troy, especially southeast of HVCC,
it may be faster to take Route 43 directly without bothering with Route
2 traffic. You're on your own for it, but it will be faster.
Once the trail reaches Sperry Road, we've got the first side trip. March Cataract Falls is a mile down a steep side trail, which means another mile of climb on the way back up. If the Hopper Trail is giving you a lot of trouble, I'd recommend skipping this one. Continuing on up, we reach and turn onto the Overlook Trail, which has a number of views out over The Hopper. This part is much easier, as the Overlook Trail mostly slabs the hillside and only climbs gradually. When we cross Notch Road, the second optional side trip is 0.2 miles down hill. Robinson Point gives arguably the best views of The Hopper in the entire reservation. Unless you're in really rough shape, I'd recommend taking this one.
Eventually, the Overlook Trail reaches the Appalachian Trail. The AT goes straight to the summit. When you reach the AT, you're quite literally almost to the top.
If anyone has serious trouble and simply can't go on, stopping at the summit is a real possibility. Bascom Lodge used to have a pay phone and presumably still has plenty of places to sit and relax while waiting for a ride to come up the road to the summit. However, unless you're really feeling dead, I'd recommend that you keep pushing. It's all downhill from here, and most of it is easy ridgeline travel, with very little rugged, difficult trail.
Before leaving the summit, sign in at the register. This helps us - or rescue teams! - pinpoint your location if something goes horribly wrong.
From the summit, we take the AT north along the ridgeline. Along the way, we go over the summits of Mt. Fitch and Mt. Williams. These are additional summits of Mt. Greylock, not mountains in their own right. (The technical requirements for being considered separate mountains are a vertical drop of at least 400 feet between the summits, or a horizontal separation I can't recall offhand.) You may not even notice Mt. Fitch. Do take the time to sign in at the register at Mt. Williams. (OK, OK, I lied - it isn't all downhill from the summit!)
After Mt. Williams, the AT heads downhill to the Money Brook Trail. We take this one down to the cars. On the way, we parallel the Money Brook for most of the descent, catching several decent waterfalls along the way.
As always, all mileages are taken from the parking area. Total distance, assuming no side trips are taken, is 12 miles. March Cataract Falls adds 2 miles (round-trip). Robinson Point adds 0.4 miles. My cumulative mileage figures will only show the main route.
From the parking lot, walk past the gate onto the Hopper Trail and follow a flat, grassy lane 0.2 mi. to where the Money Brook Trail leads straight ahead (0.2 mi.). Bear right with the Hopper Trail, ascending an old logging road, somewhat steeply at times, another 2 mi. until you reach Sperry Road (2.2 mi.).
For the March Cataract Falls side trip (2.0 miles round-trip), turn left and walk the road 0.1 mi.; just before the parking area on the right, turn left on a dirt campground road. Walk about 200 feet, past the Chimney Group Camping Area, and turn left at the sign for the March Cataract Falls. It leads a mile, descending through switchbacks, to March Cataract Falls, a 30 foot falls which usually maintains a nice flow even during dry seasons. Return the same way.
Back on Sperry Road, turn left, and walk about 100 yds past the parking area (on the right), then turn left at a sign onto the Hopper Trail. The wide path climbs at a moderate grade past a short falls. Where the Deer Hill Trail diverges right, bear left. At about 3.2 mi., where The Hopper Trail makes a sharp right, turn left onto the Overlook Trail. You will reach the first view of The Hopper within minutes, though trees partially obstruct it. A half mile down the Overlook Trail (3.7 mi.) lies the second view, which is better; Stony Ledge is visible across The Hopper to the west. Continue on the Overlook Trail to the paved Notch Road, 1.2 miles from the Hopper Trail (4.4 mi.).
For the Robinson Point side-trip, turn left and walk the road downhill 0.1 mi., past a day-use parking turnout, then turn left onto a trail marked by blue blazes. It descends steeply 0.2 mi. to Robinson Point, and a view of The Hopper superior to anything on the Overlook Trail. Return the same way.
Back to Notch Road, cross the road on the Overlook Trail and follow it uphill 0.4 mi. to the AT (4.8 mi.). Turn left on the AT, following it across the parking lot to the summit (4.9 mi.), where you'll find the War Memorial Tower and the Appalachian Mountain Club's Bascom Lodge. The best views are to the east from the meadow beyond the tower; there are also good views to the west. You can take the narrow, circular stairs up the tower for its panoramic vistas.
From the tower, follow the AT north. About a mile from the summit is a good view to the east. At 2.4 mi. from the summit (7.3 mi.), a side trail leads left to Notch Road, but continue 0.2 mi. straight ahead on the AT over Mt. Williams (7.5 mi.), one of Greylock's summits. The AT swings left here, descending easily 0.9 mi. to Notch Road (8.4 mi.). Cross the road, and 0.1 mi. into the woods, turn left onto the Money Brook Trail (8.5 mi.); in 0.2 mi., pass a short side path leading to Wilbur Clearing Shelter (8.7 mi.).
If you're curious about what the typical AT shelter is like, Wilbur Clearing is a decent example. Feel free to stop on down to it. Leaf through the shelter register if you like; add your own entry if you want. During my hike on the Long Trail back in August '99, I slept in shelters like this almost every night. The shelters varied from little run-down lean-tos sleeping 6 (sometimes smaller!) to huge enclosed cabins with bunks for more than 30. Wilbur Clearing is typical.
Back to the trail, you'll reach a side trail 0.7 mi. past the shelter spur trail, leading a short distance to spectacular Money Brook Falls (9.4 mi.). From that path, the Money Brook Trail follows Money Brook through a wild, narrow valley, with a few crossings that could be tricky in high water. Nearly a mile from the falls, the Mount Prospect Trail branches right (10.3 mi.); stay on the Money Brook Trail another 1.5 mi. to the Hopper Trail, passing a dispersed camping zone just before reaching the Hopper Trail (11.8 mi.), then continue ahead 0.2 mi to return to the parking area (12.0 mi.).