You don't need to know much about Baltimore's National Aquarium other than that it's one of the region's world-class family attractions. You and your kids are likely to want to go there often. From the massive first-floor "Wings in the Water" exhibit (with the nation's largest gathering of sting- and other rays) to the five-level Atlantic coral reef finale (you descend walkways surrounded by a 335,000-gallon tank loaded with sea life, including dozens of sharks), this may be the most spectacular water-life exhibit you'll ever witness. However, you will pay for the privilege, both with cash and, depending on how you plan your attack, crowds and other creature discomforts.

Access is controlled by timed-entry tickets, so we suggest buying your tickets in advance through Ticketmaster or online at the museum's site. Otherwise, you'll run the risk of arriving at 10:30, standing in line for an hour, and then learning that the first available tickets are for 3 (or, worse, that you've been shut out completely).

Also, we recommend locals visit on weekdays or winter, spring and fall weekends, as summer crowds can be unpleasant. Finally, each aquarium entry ticket includes a pass for a specific dolphin show held in the Marine Mammal Pavilion; the shows are usually timed so that you have an hour or more to tour the aquarium first. While the shows are good, they lean more toward education and conservation issues than the kind of raw circus-animal thrillathon you might find at Sea World. Small kids may be bored.

-- by John Kelly and Craig Stoltz

Words to the wise: It may be hard to get kids out of the first-class Aqua Shop with your credit card intact. Discuss spending limits in the car. Also, if you think you'll visit a few times a year, consider a annual family membership. It lets you walk in a special entrance without buying a ticket or waiting in line.

Notes: Strollers are not permitted. Backpacks are available to borrow for free for kids under 25 pounds.

Food: The Pavilion Cafe offers lunch and snacks, though it's predictably crowded at lunchtime. The Inner Harbor's many eateries are nearby, as are the wonderful restaurants of Little Italy.