On October 21, 1959, on New York City’s Fifth Avenue, thousands of people line up outside a bizarrely shaped white concrete building that resembled a giant upside-down cupcake. It was opening day at the new Guggenheim Museum, home to one of the world’s top collections of contemporary art.

Mining tycoon Solomon R. Guggenheim began collecting art seriously when he retired in the 1930s. With the help of Hilla Rebay, a German baroness and artist, Guggenheim displayed his purchases for the first time in 1939 in a former car showroom in New York. Within a few years, the collection—including works by Vasily Kandinsky, Paul Klee and Marc Chagall—had outgrown the small space. In 1943, Rebay contacted architect Frank Lloyd Wright and asked him to take on the work of designing not just a museum, but a “temple of spirit,” where people would learn to see art in a new way.

Over the next 16 years, until his death six months before the museum opened, Wright worked to bring his unique vision to life. To Wright’s fans, the museum that opened on October 21, 1959, was a work of art in itself. Inside, a long ramp spiraled upwards for a total of a quarter-mile around a large central rotunda, topped by a domed glass ceiling. Reflecting Wright’s love of nature, the 50,000-meter space resembled a giant seashell, with each room opening fluidly into the next.

Wright’s groundbreaking design drew criticism as well as admiration. Some felt the oddly-shaped building didn’t complement the artwork. They complained the museum was less about art and more about Frank Lloyd Wright. On the flip side, many others thought the architect had achieved his goal: a museum where building and art work together to create “an uninterrupted, beautiful symphony.”

Located on New York’s impressive Museum Mile, at the edge of Central Park, the Guggenheim has become one of the city’s most popular attractions. In 1993, the original building was renovated and expanded to create even more exhibition space. Today, Wright’s creation continues to inspire awe, as well as odd comparisons—a Jello mold! a washing machine! a pile of twisted ribbon!—for many of the 900,000-plus visitors who visit the Guggenheim each year.