St. Louis Cathedral is the oldest continuously active Roman Catholic cathedral in the United States, and its three grey spires have defined the skyline of the French Quarter since the eighteenth century. The building you see today was completed in 1794 after a catastrophic fire destroyed most of the French Quarter, and it was substantially enlarged in 1851. The interior is suitably grand — gilded vaulting, painted murals depicting scenes from the life of St Louis, and an ornate high altar that catches the light on sunny mornings.
Entry is free, and the cathedral is open most of the day. Early morning is the quietest time, before the tour groups arrive and when the light through the windows is at its best. The cathedral faces directly onto Jackson Square, making it the centrepiece of the most photogenic view in New Orleans. Evening mass is worth attending for the music and atmosphere.