Bike Tours of Lima was such a great way to spend our last day in Peru. We only had the bikes for two hours, but the guide gave us a map of where to go (we are in good shape and biked at a clip). We saw some city ruins of pre-Incan tribes, cruised along the closed street of Arequipa Avenue, and had some fun at a dirt bike/skate park. The bike tour was a fantastic way to see the city and get in some exercise. We saw beautiful parks, history, and how much emphasis on health Lima puts on its citizens.
The beach side trail is isolated to only pedestrians and bikes/skateboards/etc. so you didn't have to worry about traffic for a large stretch of our ride. (You could spend two hours on just the beachside track alone, but we ventured into the city.)
Much to our enjoyment, there was a three-mile stretch of Arequipa Avenue that was closed so people and kids could enjoy the street. There were free yoga classes in the park, small tennis courts, free water stations, and more all for free. It was awesome to experience it and they to enjoy that every Sunday from 9am-1pm! Best of all, Lima is flat so it was an easy ride (even though we were riding at a quick pace).
Definitely a must for someone that wants a little exercise and get off the beaten path!