Coun Sarah Tattersall led the ceremony at Moorend Lane in Silkstone Common.
The works followed a £745,000 grant from Department of Transport via Sustrans National Cycle Network Improvement projects.
The upgraded surfacing includes 5,642 sq m of Flexipave, a product made using recycled tyres.
As a result, 15,064 old car tyres were recycled instead of going to landfill which saved 331,411kg of CO2.
Coun James Higginbottom, cabinet spokesperson for environment and highways, said: “Active travel is a vitally important part of creating the greener, cleaner and more sustainable Barnsley we all want to see.
“Walking, running, cycling and scooting more helps you to be healthier and it’s better for the environment.
“We’re working hard to make sure our borough will have different ways of connecting our places and people.
“We know those who use the Trans Pennine Trail recognise just how valuable it is.
“I hope these improvements encourage even more people to get out and enjoy the benefits of active travel, whether it’s to get them where they need to be, or just to enjoy being out getting exercise in the fresh air.”