Building a coliseum, is there anyway to make it perfectly round ?

So basically I have built the arch and a pillar and want to use the same modal 72 times for a perfect 360 degree circle. Is there a way in which I can use an array instead of doing it all manually at 5 degree intervals ? Any help would be awesome as I takes a lot of time and effort to do this 216 times for a 3 tier let alone doing the inside as well. Any help would be awesome

Make a circular array using a rotated empty as the object offset

Note that coliseums are not actually circular


circular_array.blend (96.7 KB)