Gardaí were alerted after a member of the public spotted the bomb at the Old Mallow Road near Blackpool last Saturday morning.
When gardaí arrived they found the device lying on the road between the old Garda station and a nearby bridge, and removed it to Mayfield Garda Station.
The following morning it was taken to a secure area at the back of the station, where army bomb disposal experts from Collins Barracks rendered it safe.
They informed gardaí it was a viable device, understood to have included a power source, ball bearings and gunpowder.
Superintendent Tom Myers is leading the investigation and said it remained unclear what the device was going to be used for.
He said that while it could have fallen from a passing vehicle, gardaí were keeping an open mind on the case.
Supt Myers said the device was taken yesterday to Garda headquarters in Dublin where it was to be analysed by experts.
Pipebombs have been discovered on a regular basis in Limerick and Dublin, but they are rarely found in Cork.
“At this stage we simply don’t know what it was intended to be used for. The investigation is ongoing. We have carried out searches in the area and we are also conducting house to house inquiries,” said Supt Myers.
He said detectives were also trawling through CCTV footage to see if they can identify how the device got to be there.
Supt Myers said that anybody with information about the bomb should immediately contact Mayfield Garda Station at 021 4558510.