Taking place at Kennington Reservoir every Saturday morning at 8am, parkrun had its biggest ever attendance last weekend with 253 runners conquering the five kilometre course.

Kennington Reservoir parkrun co-event director Kathleen Fair said a whole range of ages and abilities participate in the event, from infants in their prams to people approaching 90 years of age.

"Average participant time is getting slower.

"That means people who might not be fast runners are finding us and are participating," Ms Fair said.

Whether you choose to walk or run the course is up to you, with times taken as a way to measure performance over time.

"The time goal is totally your own.

"It is a competition with yourself and used as a goal setting initiative," Ms Fair said.

There is no cost to participate, with people asked to register online before attending.

"That produces a sheet of barcodes, which get printed and is brought to any parkrun event.

"The same barcode is used globally, wherever you choose to run.

parkrun began when 13 runners got together in the English city of Teddington in 2014.

Since, it has grown into a global venture and 20 countries now take part, with Australia's first parkrun on the Gold Coast in April, 2011.

People who have participated in 50, 100, 250 or 500 events are given the chance to order a free t-shirt to recognise their achievements.

The Kennington Reservoir parkrun course starts on the Reservoir Road side of the reservoir at the main barbecue.

It then goes up Cousins Street, down through the middle of the bush and around the reservoir, with one full lap of the reservoir itself.

The course doesn't cross any roads.

"We have had people participate in wheelchairs as well.

"It is a disabled friendly course and a real community," Ms Fair said.

To learn more visit Kennington Reservoir parkrun on Facebook and parkrun.com.au to register.