It's Lights Out For The Gateway Arch Until October

ST. LOUIS, MO — It's lights out for the Gateway Arch for the rest of September, the National Park Service announced Wednesday. Starting September 17, the lights illuminating the arch at night will be turned off to avoid confusing birds heading south for the winter.

"The end of September is the peak migration period for birds migrating south for the winter," said Gateway Arch National Park deputy superintendent Frank Mares. "In order to avoid the possible disorienting effect of the monument's upward lighting on birds that migrate at night, the Gateway Arch's exterior lights will be turned of for the last two weeks of September."

The lights will back on at 7 p.m. on October 1 and stay on through the winter, officials said.

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The Arch's lighting system was recently upgraded during the park's renovation. According to a press release, 44 outdated fixtures were replaced by 26 static xenon sky lights with custom lenses. Those lenses allow more light to be focused on the arch itself with less spilling over into the surrounding sky. The result, officials say, is more greater light coverage and increased energy efficiency.

Photo by Michael Heiman/Getty Images