Sir, – The large circular structures visible from the sky in Navan would seem to push the origins of local planning in Ireland back by several thousand years ("Archeologists discover evidence of Iron Age temples at Navan Fort", News, July 17th). The modern descendants of these structures are still evident in almost all Irish towns, of course, and are usually now referred to as "roundabouts". – Yours, etc,
BRIAN O’BRIEN,
Kinsale, Co Cork.