YORK Archaeological Trust - the organisation behind the Coppergate dig and the Jorvik Viking Centre - turns 50 this year.

To celebrate, the Trust’s founding member and former director, Dr Peter Addyman, has been writing a book looking back at the last fifty years.

He has been trawling through the Trust's extensive photography archive to illustrate the book - and the Trust has sent us a selection of the photographs that he has dug out.

They include one showing the moment the famous York Helmet - one of only six Anglo-Saxon helmets anywhere in the world known to have survived to the present day - was actually discovered, during the Coppergate dig.

York Press:

The moment the Coppergate Helmet, also known as the York Helmet, was found

Other images show Prince Charles climbing down a ladder to take a close look at the dig - and Magnus Magnusson taking a look at the site.

Dr Addyman's book - 50 Years of York Archaeological Trust - will be launched on September 30 at a special gala dinner at Merchants Adventurers Hall. The Trust will mark its 50th birthday on October 1.

It was actually York's chronic traffic congestion which led to the York Archaeological Trust being set up. In 1971, an inner ring road was being proposed for the city. Dr Addyman was commissioned by York Philosophical Society and the Council for British Archaeology to write a report on the potential archaeological impact. His report included a call for the city to have its own excavation unit to help record and preserve archaeology.

The money was found, and York Archaeological Trust was established in 1972. The Trust now has offices in Sheffield, Nottingham and Glasgow, and has been involved in over 870 excavations and 2400 watching briefs - as well as managing the Coppergate dig and opening Jorvik.

York Press:

Queues to get into Jorvik in 1984

Dr Addyman admitted that writing the new book had been a 'wonderful ride through time'.

"I have re-visited hundreds of excavations, re-living important discoveries about Roman, Anglian, Viking, medieval and later York," he said. "I have marvelled again at great treasures from the digs - and I have called to mind the thousands of people, many on the Trust's staff, but many more as volunteers and friends of the Trust, whose labours and skills made it all possible."