The coliseum was made up of hundreds of arches that were used for building up higher without the building collapsing. Which meant they building would last longer. The coliseum could hold about 45,000 spectators but if everyone stood then it could hold 70,000 spectators. Most of the games held at the coliseum resulted where one man stood. At the end of the games if the gladiators won then the crowd would vote to see if the gladiator should live or die. There was a dome over the museum to block the sun on very sunny days and if it was raining to block the rain. The Romans could flood the coliseum and have naval battles. The coliseum was important because the Romans had to be entertained in some way and the coliseum was built for entertainment. Also the coliseum was a way to show that the king had power. The coliseum was mostly built out of concrete. Wealthy Romans would bet on the people they thought would win.