With 30 miles (48 km) of tall black temporary fencing, 25,000 law enforcement officers and security checkpoints set up to process hundreds of thousands of spectators, Washington is braced for President-elect Donald Trump's inauguration next week.

The Monday swearing-in on the steps of the U.S. Capitol and parade to the White House will follow a weekend featuring protests by Trump's opponents and parties and rallies by the Republican's supporters.

The inauguration follows a campaign marked by two attempts on Trump's life - including one from a would-be assassin who nicked his ear with a bullet - and a pair of New Year's Day attacks on ordinary Americans. In one, 14 people were killed and dozens injured when a U.S. Army veteran rammed a truck into a crowd of New Year's Eve revelers in New Orleans. The same day, an active-duty U.S. Army soldier detonated a Tesla Cybertruck outside a Trump-branded hotel in Las Vegas, killing himself."We are in a higher-threat environment," said U.S. Secret Service Special Agent in Charge Matt McCool at a Monday press briefing.

The inauguration itself, when Trump formally takes the oath of office with members of Congress, the Supreme Court, his incoming administration and tens of thousands of others looking on, will take place on the Capitol steps, facing the Washington Monument.

That is the same spot where, on Jan. 6, 2021, thousands of Trump supporters smashed windows, fought with police and sent lawmakers running for their lives in an attempt to overturn his 2020 election loss to Democratic President Joe Biden.

Trump's 2024 election rival, Democratic Vice President Kamala Harris, conceded her defeat in the Nov. 5 contest, unlike Trump who continues to falsely maintain that his loss was the result of fraud.

FEAR OF A LONE WOLF

Security officials said they were not aware of any specific, coordinated threats to the inauguration. What they are worried about is lone wolves, such as the New Orleans attacker, or two separate incidents last week. In one, a man was arrested for trying to bring a machete into the Capitol. In the other, a man was arrested for trying to ignite a fire near the Capitol, according to U.S. Capitol Police.

"That threat of the lone actor remains the biggest justification for us being at this heightened state of alert throughout the next week," U.S. Capitol Police Chief Thomas Manger told the security briefing.

The FBI and Department of Homeland Security on Monday warned police nationwide of the risk of copycat attacks similar to the New Orleans incident.

A large chunk of downtown Washington - stretching about 2 miles (3 km) from the White House to the Capitol - will be closed to vehicular traffic, with entry points blocked with concrete barriers, garbage trucks and other heavy items.

The 30 miles of 7-foot-tall (2-meters-tall) black fencing, designed to be unclimbable, will be the longest ever erected in Washington, officials said. Some 7,800 National Guard troops and 4,000 officers brought in from other police departments around the country will reinforce security.

While some residents of the city, where 90% of voters cast ballots for Harris over Trump, were readying to leave for the holiday weekend or hunker down at home to avoid the gridlock, tens of thousands of people were expected to descend upon the city for celebrations and protests.

About 70% of Washington's 34,500 hotel rooms were booked for the night of the inauguration and the night before as of last week, according to data from Smith Travel Research and shared with Reuters by Destination DC, Washington’s official tourism organization. Hotel occupancy was at about 95% for Trump's 2017 inauguration, and about 78% for former President Barack Obama’s second inauguration in 2013.

MARCHES AND RALLIES

Trump's 2017 inauguration was marked by massive protests and counter-protests. His former spokesman, Sean Spicer, famously began his tenure by claiming - contrary to photographic evidence -- that the crowd on the grassy National Mall was "the largest audience ever to witness an inauguration - period."

The Women's March the following day drew hundreds of thousands of people onto the streets of Washington -- and even more in pop-up solidarity events that took place around the country.

A far smaller crowd of 25,000 people is expected to take part in the anti-Trump People's March on DC on Saturday, Metropolitan Police Chief Pamela Smith said on Monday.

Thousands are expected to show up for nearly a dozen other protests or rallies that local officials have permitted between Saturday and Monday, including a Trump rally at the 20,000-seat Capital One Arena on Sunday.

Juliette Kayyem, a professor at Harvard Kennedy School who served as a homeland security official during the Obama administration, said officials appeared to follow standard practice in planning for all possibilities.

"What you're planning for is a worst-case scenario, but my suspicion is you're not going to get it, which is good," Kayyem said. "In terms of planning, it's always easier to ratchet down than ratchet up."