Below Swansea's Civic Centre, in a place where the environment is carefully controlled, sit some of the city's most ancient artefacts.

The four strong rooms contain some 250,000 documents, which take up two-and-a-half miles of space.

But few members of the public have any idea of their existence or the treasures they hold.

Nearly 900 years ago the founding charter of Neath Abbey was scripted on parchment, probably by a monk.

Written in Latin, but using a Carolingian script which was easily recognised across Europe — among the literate class at least — the framed document is carefully handled by Kim Collis, of the West Glamorgan Archive Service.

It makes you wonder what Neath was like back then. What happened to the person who wrote it? And how did the charter from 1129 find its way to a strong room below Swansea’s Civic Centre?

County archivist Mr Collis hazards a good guess at that last one.

County archivist Kim Collis in one of the 'strong rooms' under Swansea's Civic Centre

“On the dissolution of the abbey, we think the charter passed to one of the families of the Vale of Glamorgan and was preserved by one of the landed gentry,” he says.

“It came up for auction at Sotheby’s, and we bought it anonymously.”

This acquisition pre-dated Mr Collis’s arrival as a senior archivist in 1992.

It is the oldest document kept in the subterranean strong rooms.

Nearby is a founding charter of Margam Abbey, some 200 years older than Neath’s, complete with a wax seal.

The founding charter of Neath Abbey dating from 1129 the oldest item in the archives at Swansea Civic Centre.

Reaching the strong rooms means leaving daylight and descending, with Mr Collis’s bunch of keys jangling in the climate-controlled environment.

“I often compare the temperature here to a spring day, but the main thing we have to guard against is humidity,” he says.

Too much humidity and mould will grow, damaging the documents.

A sensor shows a temperature reading of 18.5C, although it feels chillier, and a 51.8% humidity level. Mr Collis seems satisfied.

The secret to the storage of such a vast amount of material is mobile racking.

Spin a wheel at the end of each rack and the whole of it slides to the side on runners, giving you enough space to access the document you’re after.

Latin writing on a document kept in the archives

Referring to the long rack we move, Mr Collis says: “That’s maybe the weight of a bus. It’s very good engineering.

“I’ve been here 26 years, and I think only one of the chains has broken.”

Staff must also protect documents from light damage, and are in the process of wrapping them in acid-free folders and boxes.

“Light is a huge problem,” says Mr Collis.

The wood pulp in paper, he explains, contains acid which slowly breaks down other elements of the paper.

The history of the Civic Centre

The Civic Centre building was constructed on the site of engine sheds and sidings beyond the entrance to Victoria rail station.

The site was earmarked by the former West Glamorgan County Council.

Planning work got under way in 1975, but it was autumn 1979 when shovels and machinery were first used in earnest.

The first phase of County Hall, as it was known then, was completed in 1982; the second phase two years later.

The building cost £18 million and the use of concrete in its design earned an award from, appropriately enough, the Concrete Society.

The layout of the four strong rooms containing the 250,000 archive documents reflects the unusual, hexagonal layout above ground.

Some of the office space at the Civic Centre is currently rented out.

Around half the documents kept in the strong rooms are from Swansea Council and Neath Port Talbot Council.

The other half are from other public bodies, such as magistrates’ courts and Church in Wales.

Before computers, this vast collection was a hard drive carrying the DNA of local civic life.

The Civic Centre under construction in the early 1980s
Pictured is county archivist, Kim Collis amongst the archives at Swansea Civic Centre.

Wandering around the racks I see huge folders marked Swansea Harbour Trust Register of Stockholders, Rhondda and Swansea Bay Railway Company, Pontardawe Rural District Council, Register of Probates, Illustrated London News, Cash Journal, Ledger, and the intriguingly-titled Pickling Machine.

I picture a Dickensian character poring over entries by candlelight.

Mr Collis and his archivist team do occasional tours of the strong rooms.

Researchers with family history, legal and academic interests often request documents and photographs to be brought upstairs.

One collection close to Mr Collis’s heart is the 8,000 illustrated plans of locomotives and mine and marine-pumping engines from the 1780s to 1880s.

Not only do they reveal exquisite drawings, they convey the global reach of Wales and Britain during that time.

Some of the mine-pumping plans were for engines destined for silver mines in Mexico and gold mines in Australia.

One drawing we look at from 1851 was covered in soot when it was acquired from the Neath Abbey ironworks.

Image of one of the locomotive drawings from the Neath Abbey ironworks collection, from 1841

Such is their importance that the collection has been entered into Unesco’s Memory of the World Programme, which protects mankind’s documentary heritage.

“It’s something that amazed me when I first came here,” says Mr Collis.

“They show how much South Wales contributed to the industrial revolution here and further afield.”

There is a network of similar archives across the UK and Ireland, and Mr Collis meets up with his Welsh archivist peers three times a year.

Asked why he felt these collections of documents were so important, he replies: “It is evidence of what we have done in the past.

“What went on is of enormous cultural and legal significance.

“If we lose our past, people don’t have a strong sense of themselves.”

The Swansea strong rooms are expected to run out of space in around 10 years, although Mr Collis and his colleagues are selective in what they accept.

Kim Collis amongst the archives

Once in a while the rooms are inspected by the London-based National Archives.

Swansea Council is planning to redevelop the Civic Centre site, but not imminently, and not before adequate provision is made for staff and services that currently operate there.

Mr Collis says discussions have been held with Swansea University about a possible joint archive facility.

As that charter writer maybe found all those years ago, time has a habit of moving on.

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