Complex sentence: Diagonally across Decatur Street downriver from the square is "Café du Monde", open 24 hours a day, well known for the café au lait with chicory and beignets served there continuously since the 19th century.
Split into simpler sentences: Diagonally across Decatur Street downriver from the square is "Café du Monde", open 24 hours a day. It is known for its café au lait, prepared with chicory, and beignets, served there continuously since the 19th century.