Overall; Detroit is famous for its music, innovation, and unfortunately its violent history.

Music;
Detroit is the home of Motown, Motown played an important role in the racial integration of popular music, as it was the first record label owned by an African American. Even if it was not the first to primarily feature African-American artists. Motown achieved a crossover success. In the 1960s, Motown and its soul-based subsidiaries were the most successful proponents of what came to be known as The Motown Sound, a style of soul music with a distinct pop influence.

Techno has its origins in and around Detroit and is often considered to have been created in Detroit.

Other-http://en.wikipedia.org/wiki/Detroit_rock#Rock_and_roll

Innovations;
The Davison Freeway was the first freeway located in Detroit

1901 The world’s first concrete road is built in Detroit

installed the country’s first traffic light in 1915 in downtown Detroit

General Motors Corp., Ford Motor Co. and the North American headquarters of DaimlerChrysler and Volkswagen are located in metro Detroit

was the first city in the nation to assign individual telephone numbers in 1879

The youngest mayor ever in the city of Detroit and the youngest big-city mayor in America (Kwame M. Kilpatrick)

founded the world’s first convention bureau in 1896

1954 The nation’s first shopping mall opens in Southfield. Northland Mall

shares the world’s first auto traffic tunnel between two nations – the Detroit/Windsor Tunnel

home to Vernors ginger ale, Sanders hot fudge, Better Made Potato Chips, Faygo soda pop, Stroh’s Ice Cream

1963 The Rev. Martin Luther King Jr. debuts his “I Have a Dream” speech in Detroit two months before its famous delivery in Washington, D.C.

Most famous event (History, Violence);

On March 6, 1863 the city of Detroit, Michigan experienced its first riot. At the time, it was reported as “the bloodiest day that ever dawned upon Detroit.”
While not as famous or destructive as riots later in Detroit’s history, the riot of 1863 was certainly a momentous occasion for the city of Detroit. The casualties of the day included at least two innocent people dead, a multitude of others, mostly African-American, mercilessly beaten. 35 buildings were burned to the ground, and a number of other buildings were damaged by fire. These numbers might not seem important by today's measure, but for a young, growing city as Detroit was in 1863, such a riot was epic in nature.

The altercations between black and white youth started on June 20, 1943, on a warm Saturday evening on Belle Isle. A fist fight broke out between a white man and a black man. The brawl eventually grew into a confrontation between groups of blacks and whites and then spread into the city. Rumors had started that a black woman had been assaulted by a white man. Another rumor was that a white woman was raped and killed by a black man. Stores were looted and buildings were burned in the riot, most of which were in a black neighborhood roughly two miles in and around Paradise Valley, one of the oldest and poorest neighborhoods in Detroit. The clashes soon escalated to the point where black and white mobs were “assaulting one another, beating innocent motorists, pedestrians and streetcar passengers, burning cars, destroying storefronts and looting businesses." Both sides were said to have encouraged others to join in the riots with false claims that one of “their own” was attacked unjustly. More than 1,800 were arrested for looting and other incidents, the vast majority being black. Thirteen murders remain unsolved.

The Riots lasted three days and ended once Mayor Edward Jeffries, Jr. and Governor Harry Kelly asked President Roosevelt to intervene. Federal troops finally restored peace to the streets of Detroit. Over the course of three days, 34 people were killed, 25 of whom were African Americans. Out of the approximately 600 injured, black people accounted for more than 75 percent and of the roughly 1,800 people who were arrested over the course of the 3 day riots, black people accounted for 85 percent.
After the riot, leaders on both sides had an explanation for the riots. White city leaders including the mayor pointed the finger at young black “hoodlums.” The Wayne County prosecutor believed that the leaders of the NAACP were to blame as the instigators of the riots. Detroit's black leaders pointed to other causes ranging from job discrimination, to housing discrimination, police brutality and daily animosity received from Detroit's white population.

(The BIG ONE);
The 12th Street riot was a civil disturbance in Detroit, that began in the early morning hours of Sunday, July 23, 1967. The precipitating event was a police raid of an unlicensed, after-hours bar then known as a blind pig, on the corner of 12th and Clairmount streets on the city's Near West Side. Police confrontations with patrons and observers on the street evolved into one of the deadliest and most destructive riots in American history, lasting five days and surpassing the violence and property destruction of Detroit's 1943 race riot, which occurred 24 years earlier.
To help end the disturbance, Governor George Romney ordered the Michigan National Guard into Detroit, and President Lyndon B. Johnson sent in Army troops. The result was forty-three dead, 467 injured, over 7,200 arrests, and more than 2,000 buildings destroyed. The scale of the riot was eclipsed only by the 1992 Los Angeles riots. The riot was prominently featured in the news media, with live television coverage, extensive newspaper reporting, and extensive stories in Time and Life magazines. The Detroit Free Press won a Pulitzer Prize for its coverage.

Over the period of five days, forty-three people died, of whom 33 were black. The other damages were calculated as follows:
467 injured: 182 civilians, 167 Detroit police officers, 83 Detroit firefighters, 17 National Guard troops, 16 State Police officers, 3 U.S. Army soldiers.
7,231 arrested: 6,528 adults, 703 juveniles; the youngest, 4, the oldest, 82. Half of those arrested had no criminal record.
2,509 stores looted or burnt, 388 families rendered homeless or displaced and 412 buildings burnt or damaged enough to be demolished. Dollar losses from arson and looting ranged from $40 million to $80 million.

Famous Events;
On February 5, 2006 at Ford Field in Detroit the Super Bowl was played,

The Detroit Electronic Music Festival (DEMF), and its successors comprise an annual series of electronic dance music showcases held in Detroit each Memorial Day weekend since 2000. Following the first three events under the name Detroit Electronic Music Festival (2000–2002) were Movement (2003–2004), Fuse-In (2005) and currently, Movement: Detroit's Electronic Music Festival (2006–present), with each name change reflecting shifts in festival management. All of these festivals continued the DEMF's traditions by featuring performances by musicians and DJs and emphasizing the progressive qualities of the culture surrounding electronic music.

I Hope this was helpful.
-DomskiiMask