Archaeologists have begun digging under the floorboards of Fremantle's historic Artillery Drill Hall in an effort to unearth some of the site's rich history.

With its distinctive curved roof, it was the first purpose-built military hall in the state when it was erected in 1895.

It was then extended during World War II.

The old drill hall in Fremantle was built in 1895. ( 720 ABC Perth: Emma Wynne )

In the 1980s it became the well-known Fly By Night Musicians Club, a much-loved live music venue that ran until 2014.

The National Trust is now undertaking restoration work on the drill hall, including lifting the floorboards and re-stumping the foundations.

As part of the works the trust has engaged archaeologists Sean Winter and B'geella Romano to investigate the underfloor history of the site, going right back to the convict era.

Painstakingly sifting layer by layer, they are tasked with finding, bagging and recording an array of objects that will help them build up a picture of the past at the site.

Dr Sean Winter is especially interested in the hall's history, particularly during the convict era. ( 720 ABC Perth: Emma Wynne )

"There are things that date from 1850 to the present," Dr Winter said.

"It's mostly just junk — but junk is what we deal with as archaeologists, that's what tells us about people in the past."

On the surface layer, many things related to the live music era have been found.

Over 400 punters crammed into the Fly By Night in Fremantle in 2012. ( 720 ABC Perth: Jarrad Seng )

"There is a range of jewellery and things that people obviously dropped while they were having a good time," Dr Winter said.

"There are guitar strings and there are heaps of Emu Export cans."

The Fly By Night club was the first venue in Australia to become smoke-free, but in the next layer down the archaeologists have dug up a multitude of cigarette packets and hundreds of matches dating from when the hall was used by the military.

"There are also sequins everywhere under this space," Dr Winter said.

"They may well date back to the Artillery Drill Hall period when this place was used for dances in the 1950s, with ladies in sequined outfits."

The archaeologists have found many old cigarette packets and matches under the floorboards. ( 720 ABC Perth: Emma Wynne )

Going deeper, a number of clay pipes have been unearthed.

"They were the cigarette of the 19th century, and they really go out of fashion and disappear from archaeological sites after about 1890," Dr Winter said.

A decorated clay pipe found at the drill hall. ( 720 ABC Perth: Emma Wynne )

Recreating a convict-era garden

Of most interest to Dr Winter is the history of the site before the hall was built, in particular the convict era garden that provided food to the inmates of the prison and the warders living nearby.

A long-term goal of his is to analyse the soil and reconstruct the garden on a site at the University of Western Australia.

Digging through the soil layers is documented by the archaeologists. ( 720 ABC Perth: Emma Wynne )

"We are going to attempt to recreate the garden using the charcoal and the seeds and the pollen that are in the soil to work out what they were growing here.

"It's really interesting to see what they were growing and using.

"We have photos of [convicts] growing — not here but in Perth — banana trees."

The items relating to the Fly By Night club will form part of a larger study by RTR community radio and Curtin University, which is investigating the history of the West Australian music industry.

Many beer cans have been found on the surface under the floorboards of the old hall. ( 720 ABC Perth: Emma Wynne )

Under-floor archaeology a great window to the past

The some of the artefacts may go on display in the future when the hall reopens as a cultural venue.

"I think the National Trust are quite keen to have any of the artefacts returned to them so that they can use them and bring them back to the site," Ms Romano said.

In the meantime, the archaeologists will continue the dirty, dusty work of digging and sifting between the stumps and girders.

Inside the drill hall as the archaeologists get to work. ( 720 ABC Perth: Emma Wynne )

"One of the great things about [being] indoors and under floors is that it is a dry environment," Dr Winter said.

"It's so dry and dusty that you get filthy, but it also means that a whole heap of stuff survives that wouldn't in other contexts — paper, cardboard, cloth, bone, cat poo.

"That's why under-floor archaeology is so great; you find things you wouldn't normally be able to find."