BBCThe annual Great South Run, due to take place in Portsmouth on Sunday, has been called off after rain and strong winds were forecast.
Race organisers said they had reached the decision after closely monitoring the weather conditions, which showed no sign of improving by the start time of the race.
The 23,000 runners who had been set to take part can roll their entry over into next year’s event or claim a refund.
The 10-mile (16km) race had been due to start at 10.15 BST.
In a statement, the organisers said: “The forecasted winds and gusts compromise our event infrastructure, including our medical facilities at the finish and around the course.
“This combined with high tide levels, potential debris and the exposure along the seafront means that we can’t guarantee the safe delivery of the event.
“Safety of our participants, staff and volunteers is our number one priority.”
Operations director Neil Gough said it was “a massive blow” for the “landmark event”.
“Many people, many volunteers, come out to support the event and the runners clearly enjoy it,” he said.
“So we are really disappointed.”
The main annual race starts from Clarence Esplanade and takes in city landmarks, including the Historic Dockyard and Spinnaker Tower.
Participant Mick Rae said he was “gutted” at the news of the cancellation.
“Totally devastated, but I think they made the right call,” he said.
“It’s a shame for everybody. It’s a shame for Portsmouth because it brings a lot of money to the city.
“But…..the winds will be horrendous and the seafront is a nightmare at the best of times.
“To me, everyone’s safe. That’s all that counts.”
Toby Lambert from Alton Sports, which sells sports goods such as trainers and clothes, is one of the traders affected by the cancellation.
“It was a huge amount of preparation from the whole team here really getting everything ready for the for the weekend,” he said.
“Disappointing, but weather can’t be helped, really.”
The race organisers said they would be in touch with all participants next week with more details about how to roll their entries over into next year’s event, or claim a refund.
Next year’s Great South Run is scheduled to take place on 19 October.
