Slíghe Chualann (Irish for 'Highway of Cualu'; modern spelling Slí Chualann) was a road in Early Christian Ireland running south across Áth Cliath ("the Ford of Hurdles"; now Dublin city) entering the territory of Cualu or Cuala before going west of the Wicklow Mountains.
[1] While George Petrie in 1839 suggested that Slíghe Chualann went from Tara to Dublin via an inland route through Ratoath, and then along the coast to Bray, County Wicklow,[2] Petrie's hypothesis is no longer supported.
Henry Morris in 1938 argues that the boggy terrain around Ratoath would not have suited chariots and cited sources for a coastal route through Swords, County Dublin as far as the Liffey.
[3] Morris goes on to trace the southern route inland, via references in Norman Irish sources to Bóthar Chualann ["Road of Cualu"].
[3] These show the Slíghe Chualann crossed back to the left bank of the Liffey near Oldbawn and ran along the west side of the Wicklow Mountains to Baltinglass and Old Leighlinbridge, then down the River Barrow by Old Ross towards Waterford.