Alexandria, Virginia—a beautiful city near Washington, D.C., that teems with historic sites and museums—has an added attraction for visitors this summer. It has joined with the U.S. Patent and Trademark Office and the National Inventors Hall of Fame on a scavenger hunt throughout the city.

The goal is to collect USPTO inventor trading cards about inventors and their patents that will be available at these nine sites in and near Alexandria: The Hall of Fame, the Alexandria Black History Museum, Stabler-Leadbeater Apothecary Museum, Gadsby’s Tavern Museum, The Lyceum, Fort Ward Museum, Friendship Firehouse Museum, Torpedo Factory Art Center and George Washington’s Mount Vernon.

As part of the event, the National Inventors Hall of Fame Museum, located at the patent office’s headquarters, has lent patent models to the nine sites for public viewing. Inventors used to have to send a model to the patent office when applying for a patent.

No prizes are offered to those who complete the scavenger hunt, which concludes at the end of Labor Day (Sept. 3). There is an admission fee to museums and sites.

The patent office moved to Alexandria in 2005 and is a major employer for the city.