why was it constructed ?
It was public memorial to United States President Abraham Lincoln.
History
The first public memorial to United States President Abraham Lincoln in Washington, D.C., was a statue by Lot Flannery erected in front of the District of Columbia City Hall in 1868, three years after Lincoln's assassination. 
what do dc stand for in washington dc District of Columbia. where is it located ? In the United States of America. name some landmarks located here ? The Lincoln Memorial, the United States Capitol, the Washington Monument and the Jefferson Pier, to name a few. how is the crime rate here ? A 2010 study found that 5% percent of city blocks accounted for more than 25% of the district's total crimes. name some sister cities of this city ? Paris and Rome. name some public transportation found in this city ? Roadways, metro and airports, to name a few. when was the fist memorial mentioned above constructed ? 1868.
It was built to honor the 16th President of the United States, Abraham Lincoln. Due to the demands for a fitting national memorial had been voiced since the time of Lincoln's death. To honor the 16th President of the United States, Abraham Lincoln
Lincoln Memorial Lincoln Memorial Lincoln Memorial
Introduction History Introduction
The Lincoln Memorial is a US national memorial built to honor the 16th President of the United States, Abraham Lincoln. Demands for a fitting national memorial had been voiced since the time of Lincoln's death. In 1867, Congress passed the first of many bills incorporating a The Lincoln Memorial is a US national memorial built to honor the 16th President of the United States, Abraham Lincoln. 
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Lincoln Memorial [SEP] History
The first public memorial to United States President Abraham Lincoln in Washington, D.C., was a statue by Lot Flannery erected in front of the District of Columbia City Hall in 1868, three years after Lincoln's assassination. Demands for a fitting national memorial had been voiced since the time of Lincoln's death. In 1867, Congress passed the first of many bills incorporating a commission to erect a monument for the sixteenth president. An American sculptor, Clark Mills, was chosen to design the monument. His plans reflected the nationalistic spirit of the time, and called for a structure adorned with six equestrian and 31 pedestrian statues of colossal proportions, crowned by a statue of Abraham Lincoln.