How large was the Roman Colosseum?

designed with a high outer wall based on three levels of arches. the inside was full of sloping seating areas for 45000 people and the seat were separated by walkway. the coloseum had no roof so to cover people from the weather they had a large canvas awning fixed at the top. the walls of the colosseum were decorated with stone coloums and statues. there wewre 76 public entrances.