So much has been happening around Harbourside – the old City Docks to many readers – over the past couples of decades that it's really refreshing to see a new publication which brings the whole 200-year-old story bang up to date.

And what could be more appropriate than its arrival on the bicentennial, the celebrations for which kick off at lunchtime today.

Museum curator and docks enthusiast Andy King and UWE academic Peter Malpass have spent a year or so researching the closely woven text and gathering in the many photos and illustrations, many of scenes which the public have probably never seen before.

They all come from the Port of Bristol's extensive collection – a real treasure trove of images – held by the city museum.

Until 40 years ago the insular world of the Floating Harbour was busy with dockers, stevedores and coastal steamers – but what was happening in the big world outside couldn't be ignored.

As Peter Malpass points out in this meticulously researched publication, motorways were taking over from the old main roads and railways and containerisation from the old wooden barrels and crates which had sufficed for centuries.

As a consequence vessels were getting larger and larger and demanding new technologies and deep water berths.

The old docks, built on a much more human scale in the romantic days of sail, were doomed and between 1969 and 1971 the city fathers decided that they had to close to commercial shipping.

From now on vessels would have to forsake the centuries old, but tortuous trip up river and use Avonmouth and the massive new dock which would be opening its giant lock gates at Portbury in a few years' time.

Shipbuilding at Charles Hill's Albion Yard – a 250-year-old tradition – came to an end in 1976.

Since the mid-1970s – very much a turning point in the life of the harbour – housing, offices, museums, arts centres, restaurants and bars have mushroomed to fill the spaces left by the old warehouses and wharves.

"The citizens who celebrated the opening of the Floating Harbour with a feast in 1809 could not have foreseen how a project carried out with a purpose appropriate to that time (shipping) could be recycled and reinvented for entirely different purposes in the 21st century," writes Peter.

"This is a continuing and evolving story. The transformation in train today is actually more radical than when the Floating Harbour was first constructed because then it was all about enhancing and developing the traditional functions of a port... now its about reinventing (the harbour) as a completely different kind of space.

"Cargo liners, tramp steamers and lighters have given way to yachts, launches and houseboats.

"Houses and apartment blocks (have) replaced sheds and warehouses (and) other buildings associated with port activities have been converted into offices, bars and restaurants.

"It's no longer a place where hundreds of men carry great planks of wood on their shoulders or heave barrels of wine or sacks of grain... (but) primarily a place for relaxation."

But as Peter points out, the most remarkable feature about Bristol's port is not so much its documented decline but its long-term survival – as facilitated by the existence of the Floating Harbour.

"The harbour," he says, "enabled the docks to continue to operate commercially for over 150 years, despite massive changes in ship design, construction and propulsion along with important changes in cargoes and cargo handling techniques.

"It was designed for short, broad wooden sailing ships but within 50 years it was accommodating a new generation of long slender ships made of iron and powered by steam.

"It should be seen as a great success... more successful than other docks constructed around that time.

"It gave a new lease of life to the existing quays, seen at the time as a real benefit to the merchants whose offices, warehouses and trading networks were located there."

With a section on dockers and stevedores, the men who actually worked the harbour, Peter and Andy have produced a thorough and workmanlike job worthy of the bicentennial.

■ Bristol's Floating Harbour – The First 200 Years, is by Peter Malpass and Andy King. Published by Redcliffe with more than 100 illustrations, the publication, which will be available in bookshops in two weeks' time, is priced £14.99.