Before you fry an egg on the sidewalk, check out a few of our favorite places to cool off, from neighborhood pools to library stacks.You’re Ready to Dive InThe smattering of free public pools may be Philly’s best-kept secret. (We think of Marian Anderson as our makeshift country club.) Though there’s not a cabana in sight, the no-frills spots (hello, concrete) are perfect for taking a dip. We recommend hitting them up during the blissfully calm adult-swim period each evening.A Must for Marco PoloNext week Making Time throws a party at the Flying W Airport Resort. Dunk in the airplane-shaped pool, admire hot hipster boys in bathing suits, and hear sets from Deerhunter, Pink Skull, and other favorites. Free shuttle buses to and from the city are a godsend when you’ve sucked down too many booze-filled water ices.Made for the ShadeOn particularly sticky nights, head to Twenty Manning Grill and request a seat at a sidewalk table beneath awnings that spray a refreshing mist. Light dishes like heirloom tomato gazpacho with pineapple-basil sorbet are tops for perking up wilting appetites. Best for BookwormsWith its icy cold air conditioning, the Parkway Central Library is a perfect place to lollygag. Roam the massive building, check out DVDs, or even take a guided tour of the Rare Books department. And if the heat hasn’t killed all your brain cells, join the summer reading program.For an AdventureLoad up the car with friends and head for Northbrook Canoe Co., about an hour outside the city. Rent inner tubes for a leisurely trip down the Brandywine, where leafy trees shade the river and prevent sunburn. Remember a pair of scroungy sneakers (our dollar store jellies slipped off within minutes) to protect feet from the pebbly bottom.Photo: Lori Greig / Flickr Swirl StealsFinish the summer strong with deep discounts on already-marked-down sandals, swimsuits, and sunnies on Swirl.