Irvine does have a "downtown", which I really meant to say was a business center, with tall buildings, hotels, and even an airport (John Wayne Domestic Airport). Irvine is the business center of Orange County. Other cities also have a business district but it's nothing like Irvine. It really is a great place to ride a bicycle whether you are on the road or on the paths. During the weekend, you can pretty much ride the business districts all to yourself. I mean, there are rarely any cars there during the weekends so you can do your intervals, "laps" around a chosen city block etc., without so much as a few cars going by. Just make sure you don't blow through any lights!

Now having said all that about Irvine, the city's layout does spoil the bicyclist into thinking he's super fit, because Irvine actually has few hills to challenge riders The Turtle Rock area is hilly but it's not THAT hilly. The hills are the territory of Mission Viejo, Laguna Hills, Laguna Niguel, and that conceited, self-absorbed city called Newport Beach.