Even the best running watches tend to struggle at the London Marathon, because some sections of the route are a nightmare for GPS accuracy. Notably the skyscrapers of Canary Wharf send watches into a tailspin, and then a couple of long tunnels make locking on to satellites impossible.
I’ve always found it a great event for testing running watches as a result, and since I was running the London Marathon 2023 shortly after the launch of the Garmin Forerunner 265 and Forerunner 965 watches, it seemed a great chance to put them head to head.
