Design expert reveals purpose of UFO-shaped circles on ground in Melbourne’s CBD

A Monash University researcher has unveiled the important role golden-coloured circles embedded into Melbourne footpaths play in the city’s development.

If you’ve ever wandered down Flinders St or Bourke St in Melbourne’s CBD, you may have noticed biscuit-sized golden circles embedded into the footpath on the edge of the road.

Known as Survey Control Marks or geodetic markers, a Monash University researcher has revealed the important purpose they hold in helping developers design and improve the city’s infrastructure.

In a 55-second clip posted to social media, video storyteller Julian O’Shea explains why these UFO-looking markers exist and how they represent property boundaries.

These markers are called Survey Control Marks or geodetic markers. Picture: Twitter/@julianoshea

“On the busiest intersections in Melbourne you might notice that there are these gold-looking circles sticking out of the ground,” Mr O’Shea says in the video.

“Or more likely – you might have never noticed them. But they play an important role in keeping the city in line. Literally.”

The designer and engineer goes on to show where some of the markers are located which include along the footpath opposite Flinders Street Station and other busy Melbourne intersections.

Mr O’Shea explains the reason they exist is to improve GPS data as the location tool can be incredibly unreliable in the city at times, making it hard for developers to pinpoint exact locations.

“[The role of geodetic markers] is to provide highly accurate known location points for planners, architects and builders,” he said.

“Knowing things like property boundaries is incredibly important to get right.”

They work by storing accurately measured co-ordinate and height information and provide a point of reference for surveying activities.

The valuable infrastructure is tracked by the Victorian Government Survey Marks Enquiry Service (SMES), with hundreds of markers littered throughout the city streets and many more spread right around Victoria.

There are hundreds of markers scattered around Victoria and they can all be tracked online via the SMES. Picture: Victorian Government

Not all are in the shape of a circle, with some covered by brass plates typically square-shaped and set in concrete or inside a rod, pipe or other stable monument for protection.

In non-CBD areas, they can be found located within road reserves, on footpaths or alongside fences.

“Permanent marks enable surveyors to easily comply with legislation and project requirements, which improves the efficiency of surveying activities, reducing costs for industry and the community,” the Victorian Government stated on its website.

Mr O’Shea then explained some people participate in the hobby “benchmarking” where they travel around the city and state to find the markers, with assistance from the SMES database.

“I think it’s amazing how much effort and skill is involved in creating a liveable city that’s home to millions of people,” Mr O’Shea told news.com.au.

Not all markers are circle-shaped. Picture: Victorian Government

“These survey markers are just one thing that keeps the city in line, literally. They’re a great example of something important, but yet something so small that most people walk over them without ever noticing them.”

Mr O’Shea said he created the video as part of his series Unknown Melbourne to help Melburnians see the city “through new eyes”.

“From the blue squares on poles around the city to help firefighters find hydrants, to the patterns hidden in the triangles in the Fed Square facade, there’s so much around us that’s worth a second look,” he said.

“I love that idea of learning new things and sharing the knowledge.”