More than 50 Lake Bolac College students, teachers, parents and community members will attempt to run, walk or bike-ride approximately 90km from Halls Gap in the Grampians to Lake Bolac.

Lake Bolac College teacher Roger Flanner said the event began in 1986 as a ploy to encourage student fitness. Then, it was known as the mountain to sea and the school's fitness elite ran or rode in teams from the Grampians to Warnambool.

This soon proved to be too great a feat, and the Lake to Mountain was established, where athletes began at Lake Bolac and finished at Halls Gap. However, Lake Bolac College funded a refurbishment of the Lake Bolac Boat Shed, and it was decided that the boat shed would provide a perfect end target for the race. That is how, 23 years later, the Mountain to Lake event has come to exist.

On the day, the runners will set off at 7am and will be followed an hour later by bike riders. They will ride, walk and run for approximately nine and a half hours, to finish at Lake Bolac in time for a barbecue and the Parents Club's famous fruit salad and ice-cream.

While bikers will usually ride the whole 90km, runners and walkers will journey in teams, with runners travelling between 11 and 16km, and walkers around six kilometres.

Mr Flanner said it's a fantastic way to get a lot of people involved in exercise.

''People who usually wouldn't exercise are getting involved, even if it is walking, it's really good to see,'' Mr Flanner said.

Each year, participants receive a t-shirt, which is designed by art and design students at the school.

''There's a bit of a competition in art classes, and the winning design is sent to Ballarat to be printed on t-shirts. Then each student can just bring in a t-shirt and get it printed,'' Mr Flanner said.

''It's a badge of honour really.''

The whole school is involved in the event, with participants ranging from as young as grade six to year 11.

''The event caters for everyone, from all ages and all levels of fitness, and it's really good to see members of the community as well as the school getting involved. Mountain to Lake has become part of our school's culture, and it's definitely something we'll continue to do,'' Mr Flanner said.