San Diego's metro system is also known as the trolley. Lots of confusion about this tour option. We were directed to the main train station by the hotel staff and several others along the way, where we could hop on and hop off the metro trains and go anywhere in the city for a few dollars per person. We had booked the Hop on Hop off Trolley tour for significantly more cost per person. We walked for several blocks from the train station in search of the tourist trolley and never found a stopping spot. When we tried to call and request a refund, we were told that the person on the phone could not help us because we bought tickets from a third party vendor. I used the info on the tourism brochure. Let the buyer beware! We were out $300 and had a lovely cab ride to the Art Deco train station and back to our hotel. So much for seeing San Diego by tour bus!