Cardiff Half Marathon 2025 Road Closures. September 30, 2025 everything you need to know about the 2025 principality cardiff half marathon. The cardiff half marathon returns to the welsh capital on sunday 6 october, with around 27,000 runners expected to take part.

Former winners, national and area champions and exciting debutants will contest the 21st edition of the principality cardiff half marathon on. Road closures for the principality cardiff half marathon on october 6.