Red Knots migrate incredible distances. For example, individuals of one subspecies (rufa) are known to travel from the southern tip of South America to the Arctic and back each year, or roughly 9,000 miles annually.
Typically absent from inland locations, Red Knots may occur by the hundreds at select coastal stopover sites, like some beaches on outer Cape Cod in Massachusetts. In contrast, here in southern Maine, the largest flock of Red Knots I've ever seen numbered 40 birds, but most often I see just a few, if I see any at all.
Though it's hard to top the beauty and easy identification of a fully red-chested adult, juvenile Red Knots are striking in their own right. However, to appreciate their white-edged back and wing feathers you'll need a close look. This is one reason birders living near the coast often carry around spotting scopes, so they can see these fine details from a distance, without putting undue pressure on the birds.