This story originally appeared on NPR. 

Putting the swing in a crucial swing state, most of Pennsylvania’s Lehigh Valley cast ballots for Barack Obama. Years later, it switched to Donald Trump and then reversed itself again to assist President Biden’s 2020 victory.

But the region swings for another reason.

Elvis Presley, Willie Nelson, Joan Baez, Johnny Cash, and Tracy Chapman are among the music giants who have played guitars made by the world’s oldest guitar maker in the borough of Nazareth.

The Martin & Co. guitar factory and museum houses a vast array of storied instruments, including vintage guitars and ukuleles dating back to 1834 and the company’s origins in Germany. Behind the museum glass at the factory’s entryway are treasured artifacts like a 1971 D12-35 that was owned for 40 years by Judy Collins and the Martin guitar that the late Kurt Cobain called, “Grandpa.”

As a nod to Martin’s history and America’s political past, a photo captures one of the manufacturer’s guitars alongside baseball legends Babe Ruth and Lou Gehrig as they campaigned for Al Smith during his unsuccessful 1928 presidential bid against Herbert Hoover.

In a place known for making things for people who make things—in industries such as steel, concrete, and textiles—the museum leads visitors into a factory that reflects Pennsylvania’s technological evolution. Across a sprawling footprint filled with guitars and their parts, a harmonious blend of meticulous hand craftsmanship is assisted by mesmerizing robotics.

Museum manager Jason Honor gave NPR a tour. Here are some images from a place that lives at the intersection between tradition and innovation.