The Rosenbach Museum and Library might be located in the middle of Center City, but it still falls off most visitors’ radars—perhaps because it’s hidden away within two 19th-century townhouses. Named for the Rosenbach brothers—one of whom was a rare books dealer, the other an arts dealer—the museum holds their thousands-strong collection of first-edition books, historical letters, paintings, and other extraordinary artifacts.

The National Liberty Museum explores what it means to safeguard liberty today—and honors the heroics of those who have fought around the world to protect democratic ideals, from Nelson Mandela to Malala Yousafzai. Offering interactive exhibitions arranged across a family-friendly scale, its galleries showcase everything from a replica of the Liberty Bell to its life-sized “jellybean children,” created as a celebration of diversity.

Though it’s located on the campus of the University of Pennsylvania, the Penn Museum is open to all—not just students. Founded in 1887, the museum holds a vast collection of archaeological and anthropological artifacts hailing from around the globe, spanning East Asia and the Middle East to Africa and the Americas, including everything from Etruscan armor to Mayan statues. It’s worth heading outside, too, to linger by its tranquil koi pond for a restful pause amid the sightseeing.

The American Swedish Historical Museum makes a memorable first impression: Tucked away within FDR park at South Philly’s southernmost edge, it was designed to resemble Ericsberg Palace and Stockholm’s City Hall. The oldest Swedish museum in the United States, it tells the story of Swedes and Scandinavians in North America, from Viking voyages to the brief New Sweden Colony, established along the Delaware River from 1638 to 1655.

Despite what its name suggests, the Fabric Workshop and Museum—founded in 1977 by art patron and curator Marion “Kippy” Boulton Stroud—isn’t just dedicated to fabric and textile arts. This boundary-pushing contemporary art museum, just across the street from Reading Terminal Market, is dedicated to the use of innovative materials more broadly, and has hosted luminaries such as Marina Abramović and Louise Bourgeois in its artists-in-residence program.

Whether the Mütter Museum actually counts as under-the-radar is up for debate—the museum’s quirk has made it something of a cult classic in recent years—but this trove of medical oddities is decidedly not the first thing visitors will associate with the City of Brotherly Love. Delightfully macabre and occasionally grotesque, the Mütter Museum was founded by surgeon Thomas Dent Mütter in 1858, and is designed to inform visitors about the human body’s mysterious ailments—and how they’re treated.

Located on Philadelphia’s northwestern edge in the tony Chestnut Hill neighborhood, the Woodmere Art Museum distinguishes itself from the city’s other art museums by dedicating its exhibitions to the region’s own art and artists. Housed in a 19th-century stone mansion, it features more than 9,000 artworks—including paintings, sculptures, and more—which span several centuries of history. The collection’s highlights include works by Mary Cassatt, N.C. Wyeth, and Benjamin West.

The Colored Girls Museum—founded by Vashti DuBois in 2015 in the Germantown neighborhood of Northwest Philadelphia—is described as a “memoir museum” that “honors the stories, experiences and history of ordinary Colored Girls.” An exhibition space as well as a research facility and place for gathering, the museum is situated within a historic Victorian house, and displays everything from clothing and jewelry to furniture and art, all of which aims to elevate girls who are too often overlooked.