Hundreds of thousands of people are expected to clog America's capital for Donald Trump's inauguration and a major demonstration the day after, but how many will actually arrive to party or protest is an open question.
Officials estimate that 800,000 to 900,000 people will be present on Friday for the inauguration, a celebration that takes over Washington DC, closing roads and taxing the city's Metro system.
Hundreds of thousands of others are expected Saturday for the Women's March on Washington.
Elliott Ferguson is president of the city's convention and tourism bureau. He says before Election Day, hotels had more events tentatively planned for a Hillary Clinton victory.
Mr Ferguson says when Mr Trump won, the "level of enthusiasm" and demand for hotel rooms did not immediately reach that of past recent inaugurations.
"No one's phones were ringing" on the day after the election, he said.
Things started to pick up after New Year's Eve but some hotels have cut back minimum-night stays from four nights to two. Some hotels are only 50% full, though higher-end hotels apparently have more bookings, he said.
"It's been much, much slower than anyone would have anticipated for a first-term president," he said.
Saturday's march has helped drive more reservations, he said.
"The moment it was confirmed it was happening in the city our hotels were seeing reservations take place," he said.
City planners are betting that Mr Trump's inauguration is more like President Barack Obama's second inauguration in 2013, which drew more than 800,000, rather than Mr Obama's first in 2009, which drew 1.8 million people.
But while officials have experience and historical data to draw on to estimate crowds for Friday, guessing how many people will show up for Saturday's demonstration is harder.
Women's March on Washington organisers said in applying for a demonstration permit that they expected 200,000 people.
Christopher Geldart, the District of Columbia's homeland security director, thinks the march will draw more than that.
Some 1,800 buses have registered to park in the city on January 21, which would mean nearly 100,000 people coming in just by bus, Mr Geldart said.
Amtrak trains into and out of the city are also fully booked on that day, Mr Geldart said.
"Usually when I look at things like that, that tells me we've got a pretty substantial crowd coming in. That leads me to believe we're definitely above the 200,000-person mark," Mr Geldart said.
In contrast, approximately 400 buses have registered to park in the city on Inauguration Day, said Terry Owens, a spokesman for the District Department of Transportation, though he said that number is growing daily.
For their part, march organisers are trying to get a headcount by asking people who plan to participate to fill out a questionnaire on their website.
That will help ensure they have the right number of things like portable toilets, medical tents and food trucks, said Janaye Ingram, who is handling march logistics. More than 100,000 people have already registered using the form, she said.
Rally, a New York City-based transportation company that connects people with bus rides to events, has organised many of the buses coming to Washington for Saturday's march.
The tally includes buses from more than 200 cities in 26 states.
The company's president and co-founder Siheun Song said the northeastern portion of the United States has "largely become sold out of motor coaches" for the day.
Demand is so great the company is using school buses to bring people to the march from Maryland, she said.
"In six years of doing business we've never seen buses get sold out so quickly," she said.
For its part, the Washington Metropolitan Area Transit Authority, which runs the city's rail and bus system, is planning an all-day effort to move people on Inauguration Day.
The system is opening at 4am - an hour earlier than normal - and running rush hour service for 17 hours until 9pm.
But the system has not seen a need to change its usual Saturday operations. The rail system will open at 7am, its normal time for the day, and run on a regular Saturday schedule.