This is not an absolute, but it's a good suggestion nevertheless. You will find out a lot more about a city using its public transportation, and you won't have to worry about parking spots or which roads to take to get to where you want to go. You will get a better idea of the layout of the city and feel like a true adventurer, as you grapple with various maps and schedules for bus, light rail, and so forth, possibly written in a delightful selection of languages that were never offered at your school. You will certainly also get more of a feel for the local color, as you'll generally be in close contact with a lot of working-class and middle-income residents of the city, some of whom will no doubt be very interested to know where you are from, how long you have been there, what you have seen, where you are staying, and if they can borrow money - possibly asked in a variety of accents and levels of intensity. You will get a glimpse of the street scene up close, as these people lean close to you and the scents of what they ate the previous day and their hygienic practices in general waft towards you, while at the same time they animatedly show you their intriguing collection of piercings, cutlery or personal firearms up close...
On second thought... taxis are pretty nice, too.
Just kidding. Really. I was in Redmond, Washington two months ago for training, and saw it only through the windows of the taxi and a car that a coworker drove, so virtually all we saw were the highways and the hotels. I went back this weekend to visit a friend and attend my first Star Trek convention, and ended up taking the bus back, and doing some walking. I got to see a lot more of the city than I ever expected to, because I went through residential neighborhoods, and as a result had a much higher opinion of it, afterwards. Besides, there's something comforting in finding similarities between you and the residents of a city.
another happily adopted nodeshell