North Dorset Trailway extension connects Blandford and Stourpaine
A new section of footpath will open later on the site of the former Somerset and Dorset railway line.
The three-mile (5km) stretch of the North Dorset Trailway between Blandford Forum and Stourpaine opens almost 50 years after the railway line closed.
The Somerset and Dorset line linked Bristol with Bournemouth and Christchurch before it closed to passengers in 1966.
The 12-mile (19km) footpath connects Sturminster Newton to Spetisbury.
Plans are under way to extend the footpath a further three miles (5km) north to Stalbridge.
The majority of the £600,000 funding for the new section came from charity Sustrans, which got cash from the Big Lottery Fund and Department for Transport (DfT).
North Dorset District Council, Dorset County Council and the North Dorset Trailway Charity also supported the scheme.