This is Londinium...

Imagine a lawless, Wild West-type frontier town, based on a trading post where the adventurous come to seek some kind of living. Open drains - effectively sewers - run along the side of the main street, giving off a foul stench. In bars, men sit drinking, gambling, swearing, fighting, throwing dice? in the street traders jostle, shout and barter. Death - particularly violent death - is never more than a few steps away. A melting pot for those looking for a brave new world.

You're probably thinking of something like Dodge City. But you'd be wrong. We're talking about London at the time of its birth. The stone villas and temples so often associated with early Roman towns couldn't be further from the truth. Rome may have been magnificent with such testaments to the achievements of Empire. London, however, was in its infancy, a far-flung outpost where life was cheap. The buildings were half-timbered with mud-brick plastering (similar to wattle and daub, a British building technique adapted by the Romans).

A new exhibition at the Museum of London offers a unique and revealing insight into what life was really like in the first years of London's development. It has been possible due to an astonishing archaeological excavation that took place in the heart of the City, on the site where High Street Londinium would have been becoming a bustling, crowded thoroughfare from around 50 AD.

This High Street - the via decumana as the Romans called it - was the Oxford Street of its day; indeed it ran along an arterial route that still exists today, Oxford Street in the west, giving way to Cheapside and Poultry in the City. At the exhibition, three buildings have been built using the techniques of the day, giving the visitor a true feel of what it was like to live in the town. The sights, sounds and even the smells are there; prepare to step back in time.

The first is a tavern and bakery, accessed via the kitchen. A frame of untreated oak stands on a mud floor without foundations. The walls were then plastered with mud brick, a technique borrowed from the native Britons. Small unglazed windows kept out the worst of the weather by means of wooden shutters. Exhibition curator Hedley Swain explains: "These buildings were, if you like, the Barratt homes of the day. They were cheap, quick to assemble and basically sound."

This was a boom period for London, with building and expansion taking place at a rate of knots. The Romans arrived in 43 AD and first made Colchester, already a British tribal centre, their capital. Within a few years they appear to have decided to make Londinium their capital and started building from scratch, "the Milton Keynes of its day" as museum director Dr Simon Thurley points out.

In 50 AD archaeological evidence shows that roads were re-routed to converge at a point about 20 metres downstream of London Bridge. This, then, would seem to be the point at which London was born. The river at this time would have been about 300 metres across (compared to 100 metres today) and over 1000 metres wide at high tide with shallow water covering lowland Southwark. The first bridge dates from between 85 and 90 AD with 20 pier bases and a central drawbridge to allow tall-masted ships through.

So we have a picture of a thriving, bustling city in its early years, a great trading centre and port. A multiplicity of races, languages, beliefs and religions could be found here at the extreme end of the known world. Life was harsh; the life expectancy, even for the rich and prosperous, was 36 years for men and only 28 for women. A quarter of all children died before their first birthday while a third would lose their father before their tenth.

The harsh struggle to survive was given occasional respite in the entertainment given by way of free plays and concerts, paid for by wealthy patrons in order to secure votes in local elections. Star names would guarantee a full house. Early versions of snuff movies were popular; if the play involved a killing, the actor's place would be taken at the last moment by a condemned man? who would then be killed on stage.

Coming back to the via decumana the visitor gets a real feel for what life was like for the citizens of this rough and dangerous town.