On n11 just past stillorgan on the left. I was on my way to work, if I was wearing my suit I’d have gone straight though! I’m trying to attach a pic. Maybe someone in the Dublin area fancies it?!!
Just for your notice . . . . . . never drive through one in Spain. The manhole covers tend to get blown out in flash floods and a lovely hole is left for your front wheel. I've seen this in Estepona and Marbella.