Many more streets will be closed to traffic downtown compared to prior inaugurations, she said.
Lanier urged people "to use really good common sense" in making plans, and highly suggested that those headed to the event not drive.
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About 3,000 police officers from across the region help patrol the event, but Lanier said there will be at least 4,000 this time from about 100 different police departments.
Lanier said the security perimeter around the inauguration will be much larger than in past years, and rolling street closures may be needed. Officials are still making decisions with the Secret Service on details.
Lanier also said officials are also making plans for the traditionally large Right to Life March in the District, which takes place two days after the inauguration.
The old Securities and Exchange Commission building downtown is being turned into Obama's transition headquarters.
Those who want to witness the swearing-in and celebrate the historic occasion also are preparing. House Delegate Eleanor Holmes Norton's staff handled about 1,000 calls Wednesday from people requesting tickets to the inauguration before creating a message directing callers to a Web site waiting list. Members of Congress will get some tickets, but not many.
"People somehow got the idea that if you call your congresswoman, you can get to go to the inaugural events," Holmes Norton said. "Where did you get that idea? Because that's wrong."
The Joint Congressional Committee on Inaugural Ceremonies will be provided free of charge and distributed through members of Congress. The tickets will be delivered the week before the inauguration. The committee does not provide tickets to the public.
No Web site nor ticket outlet has tickets.
"Any Web site or ticket broker claiming that they have inaugural tickets is simply not telling the truth," said Howard Gantman, Staff Director for the Joint Congressional Committee on Inaugural Ceremonies.
Downtown hotels and some as far as an hour away already are booked for the inauguration at expensive rates.