Arc de Triomphe
The Arc de Triomphe is Napoleon's Neoclassical take on the ancient Roman triumphal arch. It's at the center of a square, with a dozen Parisian avenues radiating out from it into the rest of the City of Light.
At the base of the arch the Tomb of the Unknown Soldier is rekindled at 6:30 each evening.
Very easy and well worth it in the time you save!