Sunday is the 9th annual Tour Dem Parks, the yearly bike ride through Baltimore’s parks and neighborhoods.

With the heat easing off, it's a great chance to enjoy the city's green gems, like Carroll, Leakin, Patterson, Clifton and Druid Hill parks. There's a choice of routes to match riders' abilities, from a 12-mile "family" jaunt up and down the Gwynns Falls Trail to the 64-mile Metric Century that's for serious road warriors indeed.

There are rest stops at Patterson, Herring Run, Druid Hill, and Leakin parks, with complimentary snacks, Gatorade and water, plus toilets or port-o-johns and even bike mechanics to help keep you rolling. And when you finish, there's a barbecue and live music at Carroll Park to wind down.

Cost is $20 for children 15 and younger, $40 per adult. Even though it's fun, it's also a fund-raiser, okay? The money goes to help gussy up the parks, print trail maps, create rain gardens and the like. For more on that, go here.

Rides start in Carroll Park, 1500 Washington Blvd, and run from 7 a.m. to 3 p.m. Go here to register in advance. If you'd rather not ride but want to be part of the scene, they're looking for volunteers to staff registration and rest stops.

(2008 Tour Dem Parks, Baltimore Sun photo by Algerina Perna)