Many roundabouts are multilane and the design in general has higher throughput than a typical intersection because drivers don’t need to stop. Traffic is always flowing.
You are right that they require a slightly bigger footprint.
The biggest roundabout I’ve personally driven was an intersection of 2 freeways and a major city throughfare. 5 lanes in the circle itself, all at speeds up to 90kph.
They’ve since added stoplights on it because people were being dumb and blowing through the whole thing at ridiculous speeds.
You are right that they require a slightly bigger footprint.
https://www.acsengineers.com.au/2016/08/22/roundabouts-vs-tr...
The biggest roundabout I’ve personally driven was an intersection of 2 freeways and a major city throughfare. 5 lanes in the circle itself, all at speeds up to 90kph.
They’ve since added stoplights on it because people were being dumb and blowing through the whole thing at ridiculous speeds.
https://images.app.goo.gl/jpzgxUyQDoqe81y38