January 13, 1982 -  Shortly after takeoff, Air Florida Flight 90 crashed into Washington, DC's 14th Street Bridge and fell into the Potomac River. Upon impact the plane hit six cars and a truck on the bridge. It tore away 97 feet of the bridge's guardrail and 41 feet of the bridge's wall. The plane plunged into the river and only the tail section remained above water. Five passengers and one flight attendant survived the initial impact and were able to swim to the surface where they clung desperately to the tail section awaiting rescue. Unfortunately emergency ground response was greatly hampered by ice-covered roads and gridlocked traffic. Some of the survivors had to wait nearly 30 minutes before being pulled from the 33 degree water. Several civilians aided in the rescue, including Lenny Skutnik, who dove into the river to assist a passenger after she had lost her grip on a helicopter rescue line and fallen back into the water. One of the surviving passengers, Arland Williams, was the first to receive a rescue line, but rather than allowing himself to be rescued he passed the line to one of the other survivors. Williams continued to pass the rescue line to other survivors each time it came to him. When the rescue crew was finally able to come back for Williams he had slipped below the surface of the water, having tread water for 29 minutes. Autopsy reports later confirmed that Williams was the only passenger to have died by drowning. The bridge was later renamed in honor of Williams. A National Geographic documentary of the accident can be viewed here.

American Fortress
 

January 15, 1943 - The headquarters of the United States Department of Defense, The Pentagon, was dedicated in Arlington, Virginia. The Pentagon is the world's largest office building by floor area, with about 6,500,000 square feet, of which 3,700,000 square feet are used as offices. It has five sides, five floors above ground (plus two basement levels), and five ring corridors per floor with a total of 17.5 miles of corridors. Approximately 23,000 military and civilian employees and about 3,000 non-defense support personnel work in the Pentagon.

January 18, 1990 -  Washington, D.C. Mayor Marion Barry was arrested by the FBI on drug charges.Federal officials had been investigating Barry for six years on suspicion of illegal drug possession and use. In late 1989, they were finally able to make a case against him.In a sting operation, in which the FBI used Barry's former girlfriend Rasheeda Moore as an informant, the FBI was able to get video footage of Barry smoking crack cocaine. Barry was charged with three felony counts of perjury, 10 counts of misdemeanor drug possession, and one misdemeanor count of conspiracy to possess cocaine. However he was only convicted of one possession incident.  Barry served six months in federal prison. Despite his criminal behavior, Barry was elected to the D.C. city council in 1992 and in 1994 was reelected Mayor.