Concorde is the largest square in Paris and it is located right at the center of it - close to many important Parisian sights. What once used to be an execution site now marks the beginning of the city's famous avenue, Champs-Élysées.
The main attraction of the square is the historical Luxor Obelisk, which is more than 3,300 years old.
When it was built in the 1750's, the square was named after the king of France - Louis XV. There was a statue of the king installed in the square but it was removed during the French Revolution.
Since it is such an iconic place, you may remember it from many films (e.g. The Devil Wears Prada).
Wikipedia https://en.wikipedia.org/wiki/Place_de_la_Concorde
Address Place de la Concorde, 75008 Paris, France
Coordinates 48°51'55.893" N 2°19'16.29" E