1872. we re often asked, you know what s the genesis of the cemetery? what the facts are is that this ground that george washington s step grandson the child he raised as his own son, when he inherited this property he built the arlington house on this high ground that we re standing on now that was the absolutely dominant terrain over the district of columbia. so it just started as the civil war in 18 1.61. there s a military necessity the army sees this property to defend. reporter: the nation began memorializing its war dead at arlington in 1868. five years later, an amphitheater was built to hold official memorial day ceremonies. this is the original amphitheater that was constructed in 1873 so 5 years, so it was ready in time for the fifth day.