In Boston, Italian tourist Federico Paliero and his girlfriend Claudia Costato peered through a closed metal gate to catch a glimpse of the USS Constitution, a wooden, three-masted U.S. Navy ship from the 18th century docked in Boston Harbor that serves as one of the city's major attractions.
Normally buzzing with tourists, the site was nearly abandoned on Wednesday, except for a handful of people looking lost and dismayed as they gawked at a sign explaining the closure.
"Italy is not the only state with money problems," Paliero said, rubbing his thumb and forefingers together.
At Great Smoky Mountains National Park in Tennessee, park staff said nearly 30 weddings scheduled for the next two weeks are threatened by the shutdown, which also sent hundreds of campers packing.
'Worried about rain'
Two dozen weddings planned at monuments on the Washington mall in October also were threatened, a park service spokeswoman said.
"I wasn't worried about the government shutting down. I was worried about rain," said bride-to-be MaiLien Le, who was planning to walk down the aisle at the Jefferson Memorial on Saturday.
Having to possibly change venues just days before her wedding is "really upsetting," she said on NBC's "Today" show.
Federal locations were also off limits for Hollywood. Film L.A., a nonprofit group that processes permits for producers of movies, TV shows and commercials, said sites including the Angeles National Forest and the Sepulveda Dam were placed on indefinite hold for filming.
About one-fifth of the classes at the Naval Academy in Annapolis, Md., were scrapped, and science laboratories at the school were shut down as furloughs for civilian Defense Department employees took hold.
Civilian workers at military bases in the United States and overseas were also furloughed, curtailing the operations of base schools, hospitals, childcare and other services.
"It saddens me to think that this shutdown is affecting those who defend our country as they strive to succeed in entering the civilian world," said Sarah Conlon, 31, who heads the Transition Assistance Management program at a base in Italy.
In northern Virginia, officials canceled federal agency blood drives that would have provided transfusions for up to 900 area patients. In Florida, the federal government's Radio and TV Marti broadcasts to Cuba were running pre-taped programming and repeats with a skeleton staff.
The U.S. Tax and Trade Bureau said it would not review or issue new permits for breweries during the shutdown.
The Library of Congress in Washington closed its doors, disrupting research projects and canceling a musical performance by Randy Newman.
The Smithsonian, which shuttered all of its museums and the National Zoo, also had to close its early childhood center even though many parents had already paid between $300 and $400 in tuition for the week, local radio station WTOP said.
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"When you have to sit down and explain to a 5-year-old why he can't go to school, it's a difficult conversation," Virginia resident Brian Katz, whose two children attend the Smithsonian Early Enrichment Center housed in the Natural History Museum, told a local Fox television station.
Juleon Rabbani, 28, got a call from the National Park Service informing him his scientific research in national parks would be shut down for now, compounding funding issues he was already facing.
"I wanted to graduate in the fall of 2014, but with my funding being held up and since my research sites are national parks, it will be well into 2015 before I am done," he said.
There were still plenty of signs of normalcy in Washington, where rush-hour traffic remained heavy and the sidewalks full. The U.S. Supreme Court was open to the public for tours as usual, and the federal judiciary remained open at least for now.
But some Washington businesses faced growing uncertainty about the length of the shutdown, which will crimp government-related events at hotels and keep many federal workers at home.
David Hill, general manager for two area hotels, said two dozen events at the hotels have been canceled in the coming weeks, including one for a large government group that triggered a $45,000 loss.
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"What I've told my team is: for us, it's business as usual ... but everything in the future is in limbo," said Hill, who manages the Phoenix Park Hotel just blocks from the U.S. Capitol and the Four Points by Sheraton near the White House.
Grain traders in Chicago were preparing to cope without weekly U.S. Department of Agriculture data on export sales typically released on Thursdays. The data, covering sales the previous week, can move prices for crops like corn and wheat if demand is unexpectedly strong or weak.
"For now, we'll go with our best guesses," said Sterling Smith, futures specialist for Citigroup.
Traders and analysts were frustrated that USDA websites went dark as a result of the federal shutdown. They mine the sites for data on crop supplies and demand to project price trends.
Terry Reilly, analyst for Futures International, said he could not complete presentations on the grain markets for clients because USDA data was unavailable.
"It makes no sense to me that they would shut down their websites," he said.