Here's the official profile of Sunday's "Stage 8" of the race. Yes, the vertical scale has been exaggerated.
Any and all visitors that are planing on coming to the observatory this weekend should expect crowds. Cycling enthusiasts are already descending upon the mountain. As of Thursday evening there were already people who had staked out camping spots (even where there isn't camping) on South Grade Road (aka S-6) and at the summit.
Thousands of people are expected to be on Palomar to watch the cyclists climb up South Grade Road, which happens to be the same road the 200-inch mirror came up in 1947. The road's 7% grade will be a challenge for the cyclists and, because they will be going slower, give fans a longer chance to watch them go by.
Visitors wishing to visit the Palomar Observatory will face multiple road closures on February 22nd. The Amgen Tour of California bike race will cause lengthy road closures on all of the roads leading to the area. It is estimated that South Grade Road (S-6) will be closed for six hours beginning at 9:00 a.m. East Grade Road (S-7) and Highway 76 will also face closures due to the event. Anyone wishing to see the Palomar Observatory, that is not already nearby to attend the event, are encouraged to find an alternate date to visit.
For those far away the event can be seen on TV and on the web at Amgen's site. I am not sure if I will see any of it, as I will be helping out the Palomar Mountain Volunteer Fire Department.
For those attending the race, we would like to remind everyone that there is no overnight parking in the observatory's parking lot.