Getting to the observatory:
Detailed information about how to get to the observatory can be found here.
We suggest avoiding Quimby Rd and instead suggest staying on I-680 and getting off at Alum Rock Rd (CA-130). The total time is about the same but the road is less windy and offers more beautiful bay area views.
If you are desperate for a bathroom break on the drive there is a portapotty at the Twin Gates trailhead about halfway up the mountain, otherwise your last chance for gas etc is when you get off of I-680 in Alum Rock.
When you reach the top, there will be parking attendants at the observatory. Let them know that you are here for Peter and Nikki’s wedding. They will direct you where to park. If you are planning to leave early let them know to ensure that you don’t get parked in. See the aerial photo below for a rough idea of how to navigate the parking lot. After the ceremony is finished you will be able to continue past the Great Lick Refractor rotunda to exit the parking lot.
