Road workers unearth 300-year-old network of smugglers' tunnels under former castle

The mysterious 10ft deep passages were discovered by water engineers carrying out routine maintenance work on pipes below a road.

The 18th Century tunnels had punched through the wall of Bridgwater Castle, which was destroyed following a Civil War siege in 1645.

They are thought to have led to cellars within the Somerset town and helped supply households with illegal and untaxed goods delivered at night by boats on the River Parret.

Richard McConnell, Project Manager with Context One, an archeological service working with Wessex Water, said : "They could have been used for some kind of clandestine movement of materials from one place to another."

But David Baker, chairman of the Bridgwater and District Archaeological Society, believes the tunnel might be 18th century sewers.

He says they could have been built big enough for a man to walk down and carry out services in the case of blockages.

Archaeologists are also excited by the discovery of the well-preserved castle walls on Wednesday, which has been hailed as an "exceptional find".

The giant stone structure, originally built in 1202 under the reign of King John, was flattened 443 years later when Parliamentarians sacked the Royalist stronghold.

The area had been the scene of a fierce battle, where Roundhead leader Oliver Cromwell was nearly shot nearly killed.

And if Lady Crystabella Wyndham, the wife of the Royalist leader Colonel Sir Francis Wyndham, had been a little more accurate with her musket the British history might have been a little different.

Eventually, with many buildings destroyed in Bridgewater, the monarchy was restored with Charles after 11 years of republican government.

In 1720 the site of the castle was bought by James Bridges, Duke of Chandos, who built a manor house.

The Duke wanted to develop and modernise Bridgwater, so he instructed the building of a modern housing development and building the tunnels.