We're not exactly breaking news by recognizing how awesome the chain of lakes is for Twin Cities runners. But Lake Calhoun, Lake Harriet, and Lake of the Isles seem to have been created for the express purpose of humans getting their move on. All three feature a three-to-four mile round trip that's ideal if you're looking to circle just one of them, and when combined, the total length is within shouting distance of a half-marathon. Workers even keep the paths nicely plowed for winter runners. Combine all that with beautiful skyline views and some of the best people-watching in town, and you won't find a more enjoyable run anywhere in the metro.