It bubbles along unnoticed, hidden beneath our streets in dark culverts or cordoned off behind concrete walls.
But fresh plans have emerged to bring parts of the River Farset back into the open air, inspired by the Belfast Telegraph's quest to locate the route of the river that gave Belfast its name.
Almost the entire length of the river is culverted beneath our feet, including the curving stretch along High Street where ships once moored as Belfast emerged as a merchant city.
Earlier this year we revealed that one open air stretch beside the ancient Shankill Graveyard is to be transformed into an amenity for local people.
Now another community further upstream has put together plans to free their stretch of the Farset from the culvert where it has run for so many years.
Inspired by our discovery of the route of one of Belfast's most important rivers, proposals to unculvert parts of the Farset have been included in the new draft Greater Ballysillan Masterplan, whose consultation draws to a close this Saturday afternoon with a family fun day event at Ballysillan Leisure Centre.
James Hennessey, associate director with landscape architects The Paul Hogarth Company, which drew up the plans in conjunction with the community, said the Belfast Telegraph's investigation proved inspirational to many in the project.
"It prompted a lot of surprise. There are so many rivers in the ground under Belfast and people aren't aware of them. The fact is that the Farset has really struck a chord because it's the river of the city," he said. "If the city really wanted to , it could do a whole lot more with its rivers.
"I think what the city needs is a strategy across the whole city to look at it holistically."
This summer, we traced the Farset from its source in a watercress-cloaked spring above Crumlin Road, down through Ballysillan Playing fields, across the Crumlin Road and the Shankill, under the Westlink and along the curve of High Street to where it emerges under the Big Fish sculpture, close to where the sandbars that lay at its mouth gave the river its name.
Now the masterplan is looking at freeing the river from its culverts through Ballysillan Playing Fields as part of a plan to get more people to use the site.
"What we want to do is try and open up as many as possible and connect them with the Belfast Hills so we will have a collection of greenways," Paul said.
"We want to really open up the River Farset and create something which looks attractive, with things like dipping pools and wildlife habitats."
The company has done something similar in Aviemore in Scotland, unculverting a town centre river and landscaping it with boulders so that it reminds people of a Highland river.