The name of Albert Einstein is associated in most peoples' minds with his theory of relativity, the equation E=mc^2, and the speed of light. Fewer people know the name of another Albert, Albert A. Michelson, who was the first American to receive a Nobel prize in the sciences. Michelson became famous in the world of physics for his heroic measurements of the speed of light, which gave experimental support to Einstein's theoretical ideas about light and spacetime.
In order to make the speed of light measurement possible, a survey of then-unprecedented accuracy had to be carried out by the U.S. Coast and Geodetic Survey. Over an air distance of 23 miles, the so-called Michelson line had to be measured to an accuracy of at least 1 part in 500,000; in the end the achieved accuracy was believed to be better that one part in a million. (The measurement is described in detail in "A Geodetic Measurement of Unusually High Accuracy", Coast and Geodetic Survey Journal, April 1949, pp. 68-74.)
Today, while Mt. Wilson is still a world-famous scientific site, Lookout Mountain is a seldom visited and largely forgotten spot in the San Gabriel mountains. Although the building and equipment that once occupied the summit are almost entirely gone, the benchmark at the east end of the Michelson line is still there, and visitors to the site can easily visualize the activity that took place there in the last century. You can clearly see the domes of Mt. Wilson in the distance and imagine Michelson's beams bridging the distance. In fact, a recent visitor has attached a light reflector to the survey monument, presumably to return modern laser beams sent over from Wilson!
Visiting Lookout Mountain today requires a serious hike. There are two common routes to the summit; one is from the northeast via Bear Flats on the Mt. Baldy Trail, while the shorter but much steeper route is to ascend the ridge from the southeast. When placing the cache, I opted for the steep southern approach. I relied on the excellent directions of my friend, hiking guide author David Money Harris:
"The most direct way to the summit of Lookout Mountain climbs a steep ridge from the south. The route is 1.6 miles one-way and involves 2300' of elevation gain with about a 3-hour round trip. By all expectations, the south-facing slope at this elevation should be an impenetrable field of chaparral. Users have maintained a narrow path through the scrub oak. The route is steep, narrow, unstable in places, and quite strenuous, but nevertheless easier than the Bear Canyon approach. It could become extremely unpleasant if the vegetation is left unchecked for a few years. Springtime is a great time to go. The scrub oak and buckthorn bloom magnificently in April and May, followed by wildflowers in May and June. By summer, the route can be unbearably hot. Watch for rattlesnakes; I saw two when I scouted the trail."
"This approach crosses private property owned by the Mt. Baldy Ranch RV Park. The property owners have agreed to allow hikers to pass in return for a modest parking fee. Please honor this arrangement and be respectful of the landowner so that hikers can continue to enjoy the privilege of using this route.
Starting from Cow Canyon Saddle, turn right (north) and drive 0.3 mile to the Mt. Baldy Ranch RV Park. Turn right at a Y in the road and follow signs 0.1 mile to park by the general store. Pay a $2 / vehicle parking fee. If the store is not open, deposit your fee in the mailbox by the door."
"Walk back to the Y, where a sign reads "Marble Head Placer Claim No. 6 Est. 1853." (GPS N34 13.914 W117 40.270 4503'). Start walking north up the fire break on the ridge behind the sign. In 60 yards, look for a use trail on the left. Leave the fire break and follow this unlikely trail as it curves around to the west side of the ridge and climbs 0.8 miles to a saddle northwest of Peak 5896' (GPS N34 14.470 W117 40.110 5432').
Two trails depart from this saddle. The trail to the right leads down into Bear Canyon. We take the trail to the left, which climbs northwest up the ridge directly to the summit of Lookout Mountain. The good use trail eventually becomes a fire break. When you reach a prominent gendarme blocking the ridge, bypass the rocks on the right, then rejoin the ridge. The upper portion of the trail becomes less distinct, braiding along multiple paths up steep loose scree past manzanita plants before abruptly reaching the flat summit."
Trailhead update as of Spring 2022: It is no longer possible to drive to the beginning of the trail; the road at Cow Canyon Saddle is blocked by a locked gate and parking is not permitted at the saddle pullout. Parking is along the road adjacent to the saddle and you'll need to walk the 0.3 mile stretch of road to the beginning of the hiking route.
You can read more about this hike and many others in Dr. Harris' excellent guidebook "Afoot and Afield Inland Empire" (ISBN 978-0-89997-462-0 http://www.afootafieldie.com/)
Don't take this hike too lightly; it is definitely not for beginners and despite the relatively short mileage is quite strenuous. Although I made the trip alone to hide the cache, in retrospect I would strongly suggest bringing along a buddy on this one. There is no cell phone reception for most of the route, so a fall or a bite in the wrong place could make for a bad day. It's a fun and scenic hike, but requires good judgement and preparation. Good lug-soled boots and protective clothing are a must, as is plenty of water. You might also want gloves for those occasional spots when hands are needed for scrambling.
Once you've reached the top and found the cache, enjoy the views in all directions and the remaining ruins. I was tempted at first to collect some of the 90-year-old fragments of broken glass, tin cans and electrical gear but I thought better of it. I could sort of feel Professor Michelson looking over my shoulder asking me to leave his mountain as it is, and I complied! Please enjoy this special place and leave it as you found it for others.
The cache container is a medium-sized ammo box stocked with some trade items and a log book.