IT is, according to organisers, the toughest open water swimming challenge in the UK.

Now a fight to the finish in a Glasgow canal is to get even bigger – with more than 1000 people set to don wetsuits for next year’s Red Bull Neptune Steps event.

The endurance event at Maryhill locks on the Forth and Clyde Canal will now cover not one but two days to accommodate the increase.

Competing in waves, entrants must sprint swim over 420 metres and climb over seven canal gates, each featuring a different obstacle.

Red Bull says it has expanded the March challenge to cater for “growing demand”.

It stated: “While the challenge has typically been dominated by endurance athletes and experienced open-water swimmers, Red Bull Neptune Steps 2020 will include a more accessible pairs relay competition. Same sex or mixed pairs can now tackle the course together, meaning competitors only need to complete half of the gruelling course which includes a 420m swim and 10.5-meter obstacle climb.”

Triathlete Erin Jeffrey, who won the women’s race in this year’s contest, welcomed the changes. On her victory, she said: “I didn’t really know what to expect going into the challenge. I was concerned about how cold the water was but once I was in, I loved every second.

“It’s a tough event that tests a range of skills, but I was able to push myself harder than I thought thanks to the cheering crowd and brilliant atmosphere of the event.

“It’s a race, so of course the competitive element is important, but results aside, it’s a huge achievement to finish.

“I would absolutely encourage anyone who is considering their next challenge to take on Red Bull Neptune Steps, it’s a unique event and a great day for spectators and participants.”