what does it represent?
It contain the remains of a dead soldier who is unidentified.
Tomb of the Unknown Soldier
The Tombs of the Unknown Soldiers typically contain the remains of a dead soldier who is unidentified (or "known but to God" as the stone is sometimes inscribed). 
mathematical concepts used in construction of gateway of india Yes, its arch has a height of with its central dome being in diameter. why was it built? t was erected to commemorate the landing of King-Emperor George V and Queen-Empress Mary. when? December 1911 who designed it? George Wittet what are his other designs? UNANSWERABLE what are its architectural features? Intricate stone latticework, elements of the Roman triumphal arch and 16th-century architecture of Gujarat. what are the examples of the second feature mentioned? Arc de Triomphe in Paris, the Narva Triumphal Arch in Saint Petersburg, the Wellington Arch in London why was the first one constructed? To honour those who fought and died for France in the French Revolutionary and Napoleonic Wars. does it have any tomb? Yes, the Tomb of the Unknown Soldier from World War I.
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Tomb of the Unknown Soldier [SEP] Symbolism
The Tombs of the Unknown Soldiers typically contain the remains of a dead soldier who is unidentified (or "known but to God" as the stone is sometimes inscribed). These remains are considered impossible to identify, and so serve as a symbol for all of a country's unknown dead wherever they fell in the war being remembered. The anonymity of the entombed soldier is the key symbolism of the monument; it could be the tomb of anyone who fell in service of the nation, and therefore serves as a monument symbolizing all of the sacrifices.