Cardiff Half Marathon 2025 Date. The race starts outside cardiff castle and runners then head down past the principality and cardiff city stadiums on the way to penarth. The principality cardiff half marathon returns to the welsh capital on sunday 6 october.
Quickly becoming one of the largest and most exciting road races in europe, the principality cardiff half marathon will be returning to the streets of cardiff on 6 october 2025. The iconic cardiff half marathon is back on 6 october 2025 with its flat, fast, road course around wales’ capital city.