Police taped off a section of the Old Tram Road near Avenham Park for around three hours on Good Friday.Advertisement
An unexploded bomb was found in a field near the River Ribble.
Dog walkers reported being turned away by officers when trying to cross the Old Tram Bridge from around 2pm.
Police vehicles were parked up by the Avenham Park pavilion.
A metal detectorist uncovered the WWII bomb between the two bridges in the park.
Part of the Guild Wheel route was inaccessible while police searchd the area. The bomb squad were called.
The mortar was detonated in a controlled explosion shortly before 5.30pm and the pathways reopened shortly after.
In April and May last year two unexploded mortars were found in the same area.