The calculated distance (air line) between Dungarvan and Dún Laoghaire is approximately 104 miles respectively 167 kilometers.
By car or train, the actual journey to Dún Laoghaire is certainly longer, as only the direct route (as the crow flies) between Dungarvan and Dún Laoghaire has been calculated here.
Air line (approximately)
167 kilometers
90 nautical miles