are there any structures similar to this tomb in the world?
Yes,  the United States unveiled its own Tomb of the Unknown Soldier, Portugal its Túmulo do Soldado Desconhecido, and Italy its "La tomba del Milite Ignoto".
Tomb of the Unknown Soldier
The idea of a symbolic Tomb of the Unknown Soldier then spread to other countries. In 1921, the United States unveiled its own Tomb of the Unknown Soldier, Portugal its Túmulo do Soldado Desconhecido, and Italy its "La tomba del Milite Ignoto". Other nations have followed the practice and created their own tombs.

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. what does it represent? It contain the remains of a dead soldier who is unidentified.
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Tomb of the Unknown Soldier [SEP] Other countries
The idea of a symbolic Tomb of the Unknown Soldier then spread to other countries. In 1921, the United States unveiled its own Tomb of the Unknown Soldier, Portugal its Túmulo do Soldado Desconhecido, and Italy its "La tomba del Milite Ignoto". Other nations have followed the practice and created their own tombs. In Chile and Ukraine, second 'unknown tombs' were unveiled to commemorate "The Unknown Sailor".