I’ve been wanting to build a round structure for a while and looked around online for various tutorials on how best to do so. One method involves stacking 1×2 bricks and 1×1 cylinders alternately, with a little twist at each placement. I made this rough 3D sketch a few weeks ago, from random bricks in my collection, just to prove the concept.

I was really wondering how best to put a roof on, and this was an early attempt to cover the top, but I was far from happy with it. Then I broke it all up and put the bits back into my parts bins.

However, today I was noodling around with the bits I got from the PAB wall at Leicester Square the other day. I remembered my sketch and thought I could use all those 1×1 trans red round plates and pink 1×2 plates to make something for my Micropolis city. Sure enough, it works just as well with plates as bricks – and by having a double stack of 1×2 bricks and 1×1 cylinders on the bottom, that gave the structure a nice lobby type area. I imagine the auditorium is in the round with seating raked up the sides of the curved walls.

The roof was still an issue until I found the bag of 1×2 curved slopes (11477) which I had picked up in November’s haul. A little bit of fiddling and I had an intricate retractable roof which we have to imagine fully covers the cylinder when closed.
I christened this MOC the Rotunda Concert Hall, and with a little bit of landscaping around the sides, it makes a lovely little 1/4 block module.