Take Sepulveda Blvd. to the Glen Anderson Fwy (105) east to the Harbor Fwy (110) north to the Pasadena Fwy, which becomes the Arroyo Parkway.
Or:
Take the San Diego Fwy (405) north to the Santa Monica Fwy (10) east to the Harbor Fwy (110) north to the Pasadena Fwy which becomes the Arroyo Parkway.
Then:
Take the Arroyo Parkway straight ahead (north); turn right (east) on Del Mar Blvd. Turn right (south) onto Holliston Ave. and park in the parking structure on the left (east) side of the street. Ask for a temporary visitor parking pass. You may park in any unnamed space.
Take the Golden State Fwy (Interstate 5) south to the Ventura Fwy (134) east to the Foothill Fwy (210) east. Exit Hill Avenue; turn right (south) onto Hill. Take Hill south to Del Mar Blvd.; turn right (west) onto Del Mar. Make the first possible left (south) onto Holliston Ave.; park in the parking structure on the left (east) side of the street. Ask for a temporary visitor parking pass. You may park in any unnamed space.
Take the San Bernardino Fwy (10) west to the Foothill Fwy (210); take the 210 west to Pasadena. Exit on Hill Ave; turn left (south) on Hill. Take Hill south to Del Mar Blvd.; turn right (west) onto Del Mar. Make the first possible left (south) onto Holliston Ave.; park in the parking structure on the left (east) side of the street. Ask for a temporary visitor parking pass. You may park in any unnamed space.
Caltech is easily accessible from both the 110 (Harbor) Freeway (southwest of campus) and the 210 (Foothill) Freeway (north of campus). Click here for maps of the local freeway system.
If you're taking the 110 freeway, follow the freeway north until it ends (becomes the Arroyo Parkway). Take the Arroyo Parkway straight ahead (north); turn right (east) on Del Mar Blvd. Turn right (south) onto Holliston Ave. and park in the parking structure on the left (east) side of the street. Ask for a temporary visitor parking pass. You may park in any unnamed space.
If you're taking the 210 freeway, exit on Hill Avenue; turn south on Hill. Take Hill south to Del Mar Blvd.; turn right (west) onto Del Mar. Make the first possible left (south) onto Holliston Ave.; park in the parking structure on the left (east) side of the street. Ask for a temporary visitor parking pass. You may park in any unnamed space.
If you've followed these directions faithfully, you should be parked in the Holliston Ave. parking structure, which is building 66 on the campus map (if you're counting). From here, you will probably want to walk to the Visitors Center (building 71) at 315 S. Hill Ave. by going north on Holliston Ave. (towards the mountains), right (east) on Del Mar Blvd., and then right (south) on Hill Ave. Student-guided campus tours begin at the Visitors Center at 2:00 PM on weekdays. More information on tours is available.
Or, if you'd like to explore the campus on your own, you can find campus maps here.