Nearly 17,000 runners took part in this year's Hong Kong Streetathon on Sunday, but some unintentionally went further than the standard distance during one of the races.

The full marathon around Victoria Harbour kicked off the races early this morning under chilly weather, as temperatures dipped to their lowest so far this winter at 16 degrees Celsius.

The day also featured a cross-harbour half marathon and a 10km race from Tseung Kwan O to Kwun Tong.

For the first time, local delicacies were dished out to runners as part of what's being dubbed a "Five-senses Marathon".

Music and fragrance diffusers also featured along parts of the route.

Tiffany, a 10km race participant, said she was delighted there was poon choi, a communal dish of foods served in layers which is often eaten on festive occasions.

"There was a band performing along the way to cheer us up, and someone gave me a high-five. There was also something to eat – poon choi with mushrooms. That could give runners a boost," she said.

For Patsy, a runner who's visually impaired, the route this time around was a bit different than last year.

"I wanted to challenge myself and see what I was capable of. The most important thing was that I had a guide who took good care of me and encouraged me," she said.

However, the 21-kilometre half marathon saw some runners go an extra nine kilometres due to unclear instructions.

James, who was among those who ran the additional stretch, said he was unable to see where to go during part of the route.

“There were traffic cones and a bunch of staff members. We couldn't see any of the signs at all," he said.

"If only one or two runners could not see the signs, then it could be their problem. But when you had more than 10 people go the wrong way, would it be an issue with the organisers?"

Organisers said they were looking into the incident to see whether there was human error involved.

Almost all of the runners who showed up finished the race, organisers said, with more than 3,000 coming from overseas.

Four participants were hospitalised, while 110 others suffered minor injuries.