Start on the top of Nob Hill at the Mark Hopkins. From our hotel on Pine, we felt like part mountain goat getting up to it. Check out the Grace Cathedral, with its bronze Ghiberti doors in front and the gorgeous stain glass windows. Walk the labyrinth inside. Outside, hop on the trolley and go down the hill to the Tadich Grill, an institution in San Francisco. If you like fish, you will be in heaven. If you don’t, the atmosphere is worth the trip. California Street is long and you will get a great feeling for the city, just by staying on the trolley.