Its long axis, oriented WNW-ESE, measures 188 metres and the short one 156.
Its coordinates are: latitude 41° 53′ 33″ North, longitude 12° 29′ 31″ East
The overall height of the building is 48,5 metres (159’)
The arena measures 76 m by 44 (249 by 144 feet, or 83 by 48 yard)
The building stands on a base of 2 steps; there are 3 floors of arcades and a 4th storey with windows (see image on the right).
There were 80 arches on every floor, divided by pillars with a half column.
The arches are 4.20 m. (13’9″) wide and 7.05 m (23’1″) high on the ground floor; on the upper floors they are only 6.45 m (21’2″) high
The seating was raised 3.60 m above the arena, and it has a gradient of 37°
The ancient capacity is calculated between 50.000 and 75.000 spectators
300 tons of metal were used for the iron clamps that connected the limestone blocks together
The ground floor, in limestone, is 90 cm thick on average
Over 100.000 cubic metres of travertine stone were used (45.000 for the external wall only)
A road about 20 km long was built to transport the travertine stones from the quarries near Tivoli
All around the top there were sockets for 240 wooden beams which supported the awning (velarium)
In 2018 the Colosseum was visited by 7,560,519 people, a record number, in 2019 there was a slight decrease, in 2020 it was closed due to Covid, but in 2021 the museums were reopened and the Colosseum Park had 1,689,269 visitors, and 16,822,074.50 Euros of gross revenue (I like that precision to 50 cents…)