FRESTON Tower, on the south bank of the River Orwell, is one of the most intriguing landmarks in Suffolk. Nobody knows its purpose and date of construction.

FRESTON Tower, on the south bank of the River Orwell, is one of the most intriguing landmarks in Suffolk. Nobody knows its purpose and date of construction.

As the Elizabethan tower and many other buildings across the country prepare to open their doors to the public this weekend, feature writer JAMES MARSTON takes a preview.

MARGARET Baldry has lived in the shadow of Freston Tower for most of her life.

In 1942 when she was aged eight, she first moved to a cottage within a stone's throw of the enigmatic red brick tower, and remembers it vividly during the war years.

She said: “I've known the tower a long while. I used to play in it as a child. It was derelict then and used for storage. There are lots of stories about why it was built and what it was used for, but no one really knows.”

More than 60 years later Margaret still lives in the village, and today she is, along with her husband John, the tower's housekeeper.

Let out to holidaymakers all year round, the tower has been owned by the Landmark Trust for the last two and a half years. Well past normal retirement age, the 73-year-old clearly enjoys her work.

She said: “My job is to hold the keys, come in and get it ready for holidaymakers - make up the beds, and sort out the laundry.”

When we arrive I open the ancient wooden door into the tower's ground floor hall, and call out a hello. A voice calls back, inviting me up the first of many spiral staircases.

Margaret is sorting some laundry in the first floor kitchen, and as I take a seat at the small kitchen table we quickly fall into conversation.

I ask about her history and she tells me she worked for Dr and Mrs Hunt, the tower's previous owners.

She said: “He was a surgeon in London and what you might call slightly eccentric. They had a place in Cambridge and they had a boat here on the Orwell. They bought the tower in 1962 and used it as a holiday home. Mrs Hunt turned it into the basic layout that it is today.

“Mrs Hunt would phone me and let me know when they were coming so I could get it ready for them. Dr Hunt used what is now the sitting room as a chart room.”

In 1999, Mrs Hunt gave Freston Tower to the Landmark Trust so, she said, “lots of people can enjoy a building where I have been very happy.” She died in Cambridge about a year ago.

We start climbing to the next level. There is a small bathroom and separate loo. Margaret tells me to open the door and have a look.

Above that is the first of two bedrooms. Margaret said: “The curtains were specially made, and show the crest of one of the original owners.”

A further bedroom is on the floor above, and from the window you can see some excellent views of the estuary, the Orwell Bridge, the rooftops of Ipswich and the surrounding countryside.

After climbing another staircase, we take a break in the top floor sitting room. The views are even more stunning.

Margaret said: “It's booked throughout the year and there's a long waiting list. You can stay for a week or a fortnight or just a weekend. I often find empty champagne bottles so I guess guests have celebrated birthdays and things like that.

“It's quite romantic and we get a lot of couples. But we also get families and groups of friends or people with boats.”

Sheltered and away from roads and the noise of town the tower is also spared television. Margaret said: “There is no television so there are a few books here in the sitting room.”

Built to be looked out of rather than lived in there are no fire places in Freston Tower.

“We had one family here at Christmas and the children were worried about Father Christmas as there were no chimneys. I told them he'll drop off the presents by helicopter on the roof and that was where they found them next morning,” she said.

I ask Margaret what it's like when the tower is open to the public.

She said: “I enjoy opening it up. We are here from 10 to 4pm. The first year we did it there were long queues and lots more than we expected. We get the place ready just as we would for holidaymakers. We are looking forward to it.”

Freston Tower is open from Friday to Tuesday . The building will be open between 10am and 4pm on September 8-11, and between 10am and 1pm on September 12.

These free open days are part of the annual Heritage Open Days on Saturday and Sunday, organised by the Civic Trust and coordinated by The Ipswich Society.

25 building will be open, including the chance to view the Town from the top of the recently vacated Civic Centre in Civic Drive. The restored Town Hall will be open, with exclusive access to the Mayor's Parlour, The Custom House, The Willis Building, Broomhill Pool, and high-tech Endeavour House, with all its eco-friendly features.

Debenham opens more buildings than any other place in East Anglia including Crows Hallwhere the new owner Caroline Spurrier recently found a coat of arms, revealing that her ancestors once lived there.

Freston Tower is one of two buildings rejoining the list this year, alongside stately Woolverstone Hall, now the home of Ipswich High School, which is open on Sunday afternoon only.

For a leaflet about all the open buildings, plus map and directions, visit libraries, the Town Hall, or the Tourist Information Centre.

The Landmark Trust is a building preservation charity, founded in 1965 by Sir John and Lady Smith.

It was established to rescue historic and architecturally interesting buildings and their surroundings from neglect and, when restored, to give them new life by letting them for holidays.

The aim of the charity is to promote enjoyment of such places by enabling as many people as possible to experience living in them for a short time. The income from letting, pays for the buildings' maintenance.

Scientific testing of selected timbers in the tower has finally dated its construction to 1578/9.

Historians agree was built while the manor of Freston was in the ownership of Thomas Gooding, a wealthy Ipswich merchant and mercer (or purveyor of fine cloths).

Gooding, who had bought the manor from Christopher Latimer in 1553, played an active part in the affairs of 16th century Ipswich. He was a typical Elizabethan 'new man' wanting to leave his mark both in architecture and dynasty.

Freston manor with its tower was inherited in turn by his son Robert and grandson Thomas. Gooding was also granted the right to bear arms in 1576, which may have provided the excuse to build this fine tower.

The plaques on the south elevation probably displayed his arms originally, which showed six red lion heads, separated by a horizontal red bar on a yellow ground.

Other than this, experts do not know why Freston Tower was built. It may have been a lookout tower against pirates or returning cargo ships, or an extravagant folly (and if so one of the earliest ones in the country), or part of a pleasure garden.

The house that stands near the tower may well have been Gooding's manor house, although it has not yet been fully studied.

A well-known but entirely fictional tale is that the tower was built for the education of the beautiful Ellen de Freston who lived in the late 15th century. Each weekday she was supposed to have studied a different subject on each floor - charity, tapestry, music, painting, and literature culminating in astronomy on the top floor.

Slightly more plausible is the theory that it was built to coincide with Elizabeth I's visit to Ipswich in August 1579, but the most likely explanation is that it was simply a celebration of wealth.

The tower was built to be looked at and out of rather than lived in - it has no fireplaces. Every opportunity is taken to allow the occupants to enjoy the views outside it - even the three-sided staircase has a window in each face on every storey, and the roof was perhaps conceived as a viewing platform from where the visitor can see up river to Ipswich and down the Orwell towards the sea.

The fact that the first three storeys on the south side of the tower are windowless suggests that the tower may have originally been joined to another building long gone.

Old photographs of the tower, reveal the shadow of such a building in this area. However, all the known illustrations and prints show it freestanding, as it is today, and our archaeological and geophysical investigations revealed no evidence of an attached building. Early photos do show that a simple porch was added later, possibly in the late 17th century, and the remaining stump has been left.

The tower changed hands and fell into disuse in the 17th century, and by the time John Ogilby drew his map of the area in 1675, it was marked as 'decayed/ruin', although the then owner, another merchant called John Wright, seems to have carried out work to the tower and house nearby.

In 1765 Freston Tower House was advertised as a treatment centre for smallpox (patients had to provide their own tea and sugar and were charged between three and six guineas a week - a lot of money for the time). In 1771, the house had become an inoculation centre against the disease, 'with opportunities for fishing, fowling etc. … boats and nets provided.'

In 1795, Charles Berners bought the estate and his family were to live at Woolverstone Hall, the main seat, until 1937, when the estate was bought was bought by the Nuffield Trust of Oxford University. Finally, the tower was bought in 1962 by Claire Hunt and her husband, who used it as a holiday home base for sailing on the Orwell.

A new leaflet for children has also been produced to explain architectural and historic details about the tower.

Freston Tower is built of red brick with blue diapers - overburnt bricks arranged in a pattern - on the north and west sides which were most visible from the river.

The staircase turret against the north wall, rises six storeys and opens on to the roof, which has an arcaded parapet, also of brick. There are polygonal buttresses at the four corners which rise to finials, and no fewer than 26 windows (and 33 if you count the blind ones).

There is one room on each floor, and a clear hierarchy to the windows and their dressings, which become more elaborate as the tower rises. The windows on the top floor are grandest, with six lights separated by transoms.

The triangular pediments to the windows on the top three floors were still quite an unusual feature in the countryside at this date, a tentative foray into Classicism.

Both the hierarchy of the windows and the remains of a primary door on the staircase on the third storey suggest that the tower may originally have been divided between service or utilitarian use on the lower three floors and more polite usage as banqueting house or folly on the top three.

These upper floors were probably hung with rich hangings in Gooding's day but no original internal features remain today, other than an apparent hearth on the first floor that turned out to be a blocked doorway to the missing building.