If you’re planning to visit the Art Institute of Chicago, I’ll give you fair warning that you may want to schedule a nap in your afternoon. With more than 300,000 works in its permanent collection, spanning 5,000 years of creativity, the gargantuan and seemingly ever-expanding campus is the second-largest art museum in the country, at nearly 1 million square feet. You’ll need to wind your way through the maze-like galleries and ancient displays of pottery and other items that people tiptoe past to get to the more popular halls.

The Art Institute is an encyclopedic art museum, which means there’s a little bit of everything, from everywhere—Indian, Southeast Asian, and Himalayan art; Chinese, Japanese, and Korean art; African art; American art; American decorative art; pottery; bronzes; sculpture; installations; modern art; miniatures and more. That’s a good thing if you’re a true art lover interested in spending an entire day here. It’s a challenge if you just want a quick walk through before packing other museums into a compact visit.

If you’re short on time, the Art Institute’s must-sees include its extensive collection of Impressionist and Post-Impressionist art, which is considered one of the finest in the world. Since 2009, the airy, light-filled Modern Wing has been showcasing the museum’s extensive collection of 20th- and 21st-century art. And two of the museum’s most beloved works are on display in the American art, pre-1950 gallery: American Gothic by Grant Wood and Nighthawks by Edward Hopper.

To help you navigate the endless halls, visit the Art Institute’s website and download the new free app, which offers 50 different tours and makes the museum feel more manageable than getting lost on your own. A separate app guides you through Impressionist works, enriching your visit with detailed descriptions of the art and the artists who created it.

If you’ve visiting with kids, stop by the Ryan Education Center in the Modern Wing, where kids and teens can sit at a workstation and get hands-on lessons from artists. Children also love the Thorne Miniature Rooms, where dollhouse-like structures, all constructed to scale, showcase European and American homes, buildings, and interiors. The Art Institute offers a variety of lectures and workshops, so check their calendar to see what’s happening during your visit.

A word of advice: The Art Institute can get incredibly crowded on weekends. If you can avoid visiting on a Saturday or Sunday, do so. Many people don’t realize that the museum is, indeed, open on Monday, which makes it a great time to visit. Also, many visitors are unaware of the late Thursday hours, so consider visiting then, too, to avoid rush hour.

If you get hungry during your visit, stop by the museum’s Caffe Moderno for soups, salads, and sandwiches, or visit Terzo Piano for a more elegant, sit-down meal. And save time for the enormous gift shop, which sells beautiful art, jewelry, accessories, books, and more. Allow at least 3 hours.