By Trolley
The San Diego Trolley (http://www.sdmts.com/Trol...), a light rail service operated by the MTS, runs through Old Town and Mission Valley. The Blue Line connects Old Town to Downtown to the south and all the way down to the Mexican border beyond that. The Green Line travels east from Old Town through Mission Valley making stops at all the shopping centers, Qualcomm Stadium, and the Mission San Diego, then continuing east past SDSU out to El Cajon and Santee.
Standard one-way fares run from $1.25 to $3 depending on how far you travel. Day passes run at $5, and there are 2, 3, and 4 day passes available. Tickets have to be purchased from the vending machines at the station before you board the train. There's no formal system to check if you've purchased a ticket, but there are trolley guards that may come around and ask to see your ticket, and the fine is normally around $120 for not having a ticket.
By car
Mission Valley is strung along I-8 and several interstates intersect with I-8 through the valley, making access by car relatively easy. Old Town is located just off the intersection of I-5 and I-8 at the western end of the valley, SR-163 intersects I-8 near the Fashion Valley shopping center, and I-805, and I-15 cross I-8 in the eastern part of the valley near Qualcomm Stadium.
Getting through Mission Valley in a car is quite painless, given the large boulevards and numerous parking lots. However, finding a`place to park in Old Town can be a real drag. Even Mission Valley's large roads can get clogged with traffic during rush hours, Chargers games, and the holiday shopping season when shoppers flock to Mission Valley's many retail outlets.