What will life be like on the UK's first migrant barge?

Three storeys high and the length of a football pitch, the hulking grey Bibby Stockholm has spent the past 30 years as an accommodation barge.

Its densely-packed rooms have previously housed asylum seekers, homeless people and construction teams working off the Scottish coast.

It is now berthed at Portland in Dorset - the first vessel secured under Home Secretary Suella Braverman's plans to reduce the cost of asylum accommodation and provide a temporary home for about 500 male asylum seekers.

Critics have likened the Bibby Stockholm to a "floating prison". They say 500 men, packed into a ship with 222 cabins, will suffer extra trauma while they wait for their asylum claims to be processed.

Sited where a prison ship used to be

Portland Port, on a scenic peninsula in south Dorset, is a destination for cruise and cargo ships.

The Bibby Stockholm's berth is beneath a steep hillside dominated by The Verne prison and the Royal Naval Cemetery.

The barge is centrally located in the same spot a prison ship was moored until 2006.

HMP Weare was used by the government to "temporarily" ease prison overcrowding.

It ended up staying for just over nine years. The Bibby Stockholm is set to be there for an initial trial of 18 months.

• Portland is a dumping ground say residents

• Why is Bibby Stockholm barge so controversial?

'Spacious bedrooms'

The vessel's owner, Liverpool-based Bibby Marine, lists 222 "spacious" cabins with natural light in its brochure. A typical bedroom includes a single bed, an en suite shower, a TV and wi-fi, the firm says.

However, the government has replaced the beds with bunk beds and has converted some communal rooms into dormitories for four to six men.

Critics, such as South Dorset Conservative MP Richard Drax, have expressed fears the barge will be vastly overcrowded, leading to unrest among the people on board.

'No alcohol to be sold aboard'

In previous deployments, the Bibby Stockholm's facilities have included a bar

"Luxury living" can be enjoyed in the well-equipped gym or by sampling the "great drinks selection" in the bar, according to Bibby Marine's website.

However, the Home Office has ruled out migrants being allowed to purchase alcohol on board. The bar has been removed.

The gym has survived the refit, along with a large canteen and a TV room with a big screen and sofas.

There is also a multi-faith prayer room and a classroom which can be used for meetings and activities.

Limited outside space includes the vessel's central courtyards and a fenced-off compound on the adjacent dock.

Shore excursions

People will have to travel through a secure cordon to enter or leave the ship

Barge residents will be "strongly encouraged" to return to the ship by 23:00 each night, the government has said. However, there will be no curfew.

The migrants are not officially detained, so their movements are "controlled within the limits of the law".

They are discouraged from roaming the streets of Weymouth or Portland, Immigration Minister Robert Jenrick told parliament.

A bus service - initially hourly - will be offered to take migrants through port security to "agreed places where they might spend some free time or go to a shop".

The shore excursions could include sporting activities, community volunteering and guided walks, Dorset Council has said.

Who are the residents?

Those on board will be single, adult males aged from 18 to 65.

The BBC understands they will be a long way into the asylum claim process. Decisions on their applications could take nine months to complete, the government says.

The first 50 men will arrive within weeks after "suitability screening".

That will include physical and mental health assessments and security checks such as identity checks against UK immigration and police databases.

How has Bibby Stockholm been used before?

The engine-less Bibby Stockholm was built in the Netherlands in 1976 and converted to an accommodation barge in the 1990s.

The triple-storey vessel is slightly less than the full length and half the width of a football pitch (93m x 27m/306ft x 90ft).

It has housed migrants before, in Germany and the Netherlands, as well as being chartered for workers on a Shetland gas plant and a Swedish wind farm.

Vessels have been "used successfully" in the past year to house migrants in Scotland and the Netherlands, the government says.

Home Office officials reportedly went on a fact-finding tour of a ferry housing migrants near Amsterdam.

One resident of that vessel told the BBC she found it "safe, clean and comfortable", but another described it as "very claustrophobic".

Health and security

Security officers will be on site at Portland Port 24 hours a day.

Dorset Council is receiving £3,500 per occupied bedspace on the Bibby Stockholm in order to provide statutory services, with additional funding provided to the local NHS and police, the Home Office said.

NHS Dorset has said the barge residents would not need to access existing health services in Weymouth and Portland.

They will instead receive care "either directly on the barge or remotely" from a team of experts "with previous experience of working with asylum seekers".

How much will it cost?

The government has declined to comment on the cost of the barge or managing the services on board.

However, it said hotels for 51,000 asylum seekers were costing the UK taxpayer about £6m/day.

Refugee campaign group Reclaim The Sea reported that chartering the vessel will cost £7.3m/year.

Factoring in other costs, it estimated the barge would initially save less than £10 per migrant per day.

However it said the savings would probably be wiped out by extra costs such as dry dock delays and barge repairs.

The Home Office said it was clear that its alternative accommodation sites, including former military bases, were cheaper than hotels.