To the uninitiated, it is a channel etched out of the ground parallel to a busy road in St Albans with trees sprouting haphazardly along its length.

But to those in the know it is an important reminder of ancient times, an Iron Age territorial boundary named Beech Bottom Dyke.

Its supporters – of which there are many – want its heritage and pivotal role during moments in St Albans’ history brought to the fore, to attract more visitors in future.

And the district council has recently signalled its intention to improve the site.

But to be fair, compared to the city’s other cultural and historical icons, St Albans Abbey and the Roman mosaic and hypocaust at Verulamium Park, it is currently the ugly duckling of local landmarks.

This is in part because of its location, tucked away near the Ancient Briton pub and screened by houses along Beech and Firbank Roads on one side.

There is no stunning vista, that ‘wow’ factor to catch the eye of visitors such as the city’s medieval belfry, the Clock Tower, or the impressive roofline of St Albans Cathedral.

On the day that the Herts Advertiser was given a tour of the earthwork by local historian Peter Burley, we had to be led to the entrance as it is hidden between houses on Beech Road.

As we trudged along the informal path Peter, a member of Friends of Bernards Heath, points out unwelcome additions to the ancient monument.

Evidence of garden waste heaved over fences bordering neighbouring back yards can be seen in places.

Peter said it was not unusual to stumble across flytipped waste. He is also concerned that some residents have built sheds right along the dyke’s boundary, disturbing the soil of the earthwork.

Under English Heritage rules a scheduled monument is protected against disturbance or unlicensed metal detecting. In certain circumstances, planning permission must be obtained before any work can be carried out which might affect a monument either above or below the ground.

If it was not for the district council, which owns and manages the dyke, clearing out flytipped and other waste, the ditch would eventually be swallowed up within 200 years, warns Peter.

He said: “If the present rate of rubbish being dumped continued without being cleared by the council, it will in theory make the dyke level in a couple of centuries.

“It is illegal to tip anything into an ancient, scheduled monument. And new growth, such as holly trees, should be managed as it is obscuring sightlines. You don’t want a mass of branches and holly trees everywhere.

“The council should be doing more to manage it. This is St Albans’ most hidden tourist asset. Everyone would like it more accessible.”

n Designated an ancient monument by English Heritage, Beech Bottom is thought to have been constructed between the mid-First Century BC and the Roman invasion of AD43.

The ditch was a key landmark during the Second Battle of St Albans (1461), when it was fortified with artillery from the Tower of London.