The Mutter Museum is a medical museum in Philadelphia, Pennsylvania, United States, that houses a collection of medical oddities, anatomical specimens, and pathological curiosities. The museum was founded in 1858 by Dr. Thomas Dent Mutter, a surgeon and professor at Jefferson Medical College. Mutter's collection was originally intended for teaching purposes, but it soon became a popular tourist attraction. Today, the museum is open to the public and houses over 20,000 specimens, including human skeletons, organs, and tumors, as well as medical instruments and artifacts.