After an extensive five-year, $4.4 million restoration, one of Los Angeles’ most celebrated architectural landmarks, the Hollyhock House, reopened to the public on Friday, the Los Angeles Times reported.

The oil heiress Aline Barnsdall commissioned Frank Lloyd Wright to build the residence in 1919. The house is a National Historic Landmark and is now owned and operated by the city.

The restoration work was initially meant to address only the most urgent problems, including a leaking roof and blocked drainpipes. However, experts soon decided to overhaul the entire structure, as the building has been exposed to a series of sub-standard quick fixes over the years. In the course of the restoration the house was returned almost to its original state intended by its legendary architect.

The city celebrated the re-opening of the architectural masterpiece by keeping it open for 24 hours. LA residents flocked to the site, and many waited in line for several hours for the chance to wander around the house and its grounds. To mark the occasion, visitors were also permitted the one-time opportunity to take photographs.

One of the visitors, Jennifer Wong, an architectural designer told the Los Angeles Times “when are you ever going to see it at night? You get to see it as if you lived there.”

The Hollyhock House, as well as nine other buildings designed by Frank Lloyd Wright, have been nominated by the United States to the United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage List. They are the first modern structures in the United States to be nominated to the UNESCO list, and include Wright’s celebrated Fallingwater in Mill Run, Pennsylvania, and Taliesen West in Scottsdale, Arizona, as well as the Guggenheim in New York.