The simplest approach to Caernarfon is by car. The A55 expressway runs along the north Wales coast — from Chester (90 minutes) and from the M6 (two and a half hours from Manchester) — and at Bangor the A487 branches south to Caernarfon, ten minutes further.
There is no mainline railway station in Caernarfon — the nearest is Bangor, eight miles north, with direct trains from Manchester, Birmingham, and London Euston (around three and a half hours from London). Frequent Bws Arriva and TrawsCymru buses connect Bangor to Caernarfon's bus station behind Castle Square. The Welsh Highland Railway runs into Caernarfon as a heritage line from Porthmadog but is not a practical mainline connection.