Climb one (Category 2) is 9,7km long and goes from an elevation of 140m to 590m (450m vertical). This sector is fairly steady for the first 6,0km (310m vertical, 5,2%), then levels off to a false-flat for 1,6km (25m vertical, 1,6%), then tips up again for the final 2,1km (115m vertical, 5,5%). I suspect this climb qualifies as Category 2 only by virtue of its length; there are short sections of the third sector that are in the 7% - 8% range, but generally the grade is something one would find on a Category 3 climb. Most of the first 7,5km of this climb is fully exposed. This makes for great views, particularly on the rare day when the haze and smog are at a dull roar in the Valley, but if the temperature is over 297°K (24°C), the heat becomes a factor. The final 2,1km is mostly shaded, which is nice, but the Lord giveth, the Lord taketh away: 8,5km into climb one, the asphalt turns into unpleasantly rough chip seal, and stays that way for the next 9,7km. A pro can clean this climb in 21:00 - 23:00; most folks amble up in 37:00 - 40:00.
Climb one is followed by a 2,0km descent that goes from an elevation of 590m to 500m (-4,8%). It is twisty for the first several hundred meters, but soon straightens out. The road is rough and has several difficult-to-see potholes. If one is aggressive, this section can be done in 3:00 - 3:30, but that is for brainless types -- young males between 15 & 25. Those outside this sociopathic demographic take 4:30 - 5:30 to get down.
Climb two (Category 3) is 5,4km long and goes from an elevation of 500m to 710m (210m vertical, 3,8%). The paper profile of this climb is deceiving. Perhaps because the bottom section is its steepest sector and one has been softened up by climb one, this is the part of the trip I find most difficult. This is exacerbated by the exposure -- 4,5km of this climb is in full sun. The shade, which is of the dappled variety provided by beautiful oak trees, is in fits and patches near the top. Another welcoming feature of the acme of this climb is the end of the execrable chip seal. From there on the asphalt is sexy smooth. A pro can do this climb in 11:00 - 13:00; most folks take 20:00 - 25:00. On the return trip, climb two is best descended with a wary eye; nearly all of the sharp corners between the 2nd and 5th kilometers are littered with significant rockfall. If fresh, this can include rocks as large as 1 liter; if the rockfall has been on the road for awhile, the crushed rock is slippery.
Climb two is followed by a 1,4km descent that goes from an elevation of 710m to 680m (-5,2%). The first corner of this downhill is particularly sharp, often with rock-litter on the pavement, but the rest is easily navigated. The above-mentioned brainless young males can do this in less than 2:00, despite a burp of a rise near the bottom. Most folks do this in 3:00 - 3:30.
Climb three (Category 1) is the doozy. It is 10,1km long and goes from an elevation of 680m to 1 280m (600m vertical, 5,9%). Much of the climb is shaded, again by the oaks, but, as one gets higher, also by pine trees. One can see the end goal -- the Observatory -- for much of the last 5km. The Observatory isn't coy; it quickly, mercifully grows larger. It has several switchbacks along the way, but there are several 100m - 200m-long "ramps" that are at a 7% - 8% gradiant. The pros can do this section about as fast as a human can run 10km on a track -- 26:00 - 27:00. Most folks take 45:00 - 55:00.
So a world-class male climber can climb Mount Hamilton in 1h00 - 1h05 (the Strava record is around 1h05, but this doesn't include the times of the mountain goats riding over it for the Tour of California), a top female in 1h15 - 1h20. Top regional riders can do it in 1h05 - 1h10. A point of pride for Joe Climber is the 1h30 barrier. Breaking 1h40 is nothing to brag about, but it would put one in good standing with most roadie snoots. Most folks who are in good shape and who have a functioning bike take 1h45 - 1h55.
The greatest reward for the long climb to the peak of Mount Hamilton is a tough call. It's certainly not the view, which is nearly always marred by Valley smog and haze. Rather, it's a toss-up between the Obersvatory's fountains, which have incredibly refreshing artesian water -- refrigerator cold and so satisfying after drinking tepid, BPA-laced water all the way up the climb -- and the near-hidden courtyard just behind the Observatory. If one comes armed with a book, some extra food, and perhaps a mat to lay on, three hours can pass by in relaxing, shade-dappled style. The Observatory itself is another gem. There are tours offered every 30-minutes in the afternoons and the self-guided tour is excellent. And one can thank the Observatory for the relatively steady and reasonable grades -- how else could horses get a monstrous telescope to the top of a mountain?
The typical temperature gradient of 6,5°K/1 000m elevation generally does not hold true for Mount Hamilton. Often there is no gradient at all in the summer -- if it's 300°K in the Valley, there's a good chance it will be the same at the Observatory. The ambient temperature in the aforementioned sections exposed to the sun is exacerbated by the heat reflecting off of California's depressingly yellow grass and the ubiquitous rock-cuts. From mid-autumn to mid-spring, though, the ambient temperature is nearly always below 295°K and there is a temperature gradient, though still less than 6,5°K/1 000m. At this time of year, even if one is packing light, it is a good idea to bring a top in the 150g/square meter - 200g/square meter range, depending on one's proclivity to shivering.
