Picture-postcard Suffolk with its ice-cream coloured houses, thatched cottages and village greens with duck ponds is hardly the sort of place one imagines aliens from outer space would choose to land. But, as modern folklore has it, in the bleak midwinter of 1980 they chose Rendlesham Forest near Woodbridge, just up the road from Aldeburgh, famed for its festivals of classical music and poetry. Rendlesham has been a Mecca for UFO enthusiasts – and the plain curious – ever since.

Local physicist Rob MacLean became interested in Rendlesham eight years ago after his son came home from school with the story. Like many, he became hooked on the mystery and began devising his own theory – that what US airmen saw in December 1980 was the combined effect of the beam of the Orford Ness lighthouse and the flashes of a now non-existent light ship.

Rob had been having email discussions with my partner, David Clarke, about this, and offered to take us around the disused Bentwaters US airbase, neighbouring RAF Woodbridge and Rendlesham Forest, and along the route taken by those who saw the UFOs. Even to a non-ufologist like myself, it was too intriguing an offer to miss.

We arrange to meet at The White Lion in Ufford. We haven’t seen Rob in the flesh before, but spot him instantly in the quiet beer garden; in aviator sunglasses and sharply pressed shirt he looks like a member of the CIA.

We order a curry and a pint and get straight down to business. Rob pulls out an Ordnance Survey map to point out the key locations of the incident. To arrive at his theory he has painstakingly calculated the angles and visibility of the lighthouse and light ship’s beams, taking into account dips in the land and the height of the trees 25 years ago. It’s all a bit mind-boggling, but I get the general principle.

First, we make for RAF Bentwaters, which Rob has obtained permission for us to visit. The base isn’t open to the public, although a museum is planned. If you are planning to visit, it’s worth ringing ahead to see if the current owners, Bentwaters Parks Ltd, will allow you onto the site.

Stripped of activity, the airbase resembles a theme park with no people. Vast open runways cut across a pancake-flat landscape on which tufts of fir trees occasionally break up the monotony of the brown, Swiss roll-shaped hangars.

Up in the lookout tower we can see the full extent of the base: the thick carpet of forest, which must have provided an ideal cover for its contentious nuclear secrets, envelops it. Bentwaters was originally constructed in 1943 for the USAAF, but underwent a great deal of expansion during the Cold War. By the time of the Rendlesham incident, in 1980, the Americans – to say the least – were more than a bit jittery.

Back on the ground, we stroll among the empty shells of buildings, dazzled by the glare of the midsummer sun on concrete. There is not a soul about. We are on ‘hot row’, where nuclear weapons were carefully guarded, though it is hard to imagine that in these echoing, turf-covered bunkers once nestled a significant strategic part of America’s Cold War arsenal. Rob pulls back the solid metal door of one bunker to reveal abandoned American cars; in another we disturb a baby barn owl.

We then venture into one of the single-storey, windowless cubes that served as a command centre. It smells of damp carpet and there are yellowing notes bearing instructions sellotaped to telephones. Portholes around eight inches square with sliding metal shutters are the only means of access to daylight. I peer out through three rows of open mesh fencing into the black heart of the forest. It’s easy to imagine how the threat of Russian attack in such a remote and forbidding place could jangle the spirits.

Rob ferries us next to East Gate on the Woodbridge base (left), where the three young airmen were the first to see strange lights in the forest. The gate is set in a high wire fence that surrounds the base, and juts out into the forest, distanced from the main area of the camp. Looming pines behind young deciduous borders form a dense, dark wall. The routes through the forest have no names, just numbers.

Picture the scene in December 1980. It is probably very cold, certainly pitch black in the forest. As Rob says, it would have been an “awfully lonely place to be posted.”

After tea, we return just as darkness is beginning to descend, meeting Rob around 9 pm at the eastern edge of the forest on a deserted road that leads to a hamlet called Capel St Andrew.

Before we set off, we sit in Rob’s people carrier listening to a recording of the UFO hunt made by Lieutenant Colonel Halt’s posse. The men sound excited, adrenaline-fuelled, their voices rising at times to almost hysterical proportions. Their Geiger counter reading was also, apparently, rising: “We found a small blast, what looks like a blasted or scruffed up area here. We’re getting very positive readings…”

I remain unconvinced. The recording suggests to me a group of men who were predisposed to find something unnatural in the forest.

The night is light and sticky with tufts of cloud. Kitted out in boots and walking jackets we venture into the field ahead of us, stumbling between rows of a leafy green vegetable we think is sugar beet. Despite the reasonably bright night, it is difficult to see where to place our feet, and Rob is reluctant to use a torch for fear of drawing attention to ourselves. After a few minutes, we decide to return to the field’s edge and try a different tack. This in itself proves difficult – we sink up to our knees in mud.

Extricating ourselves, we skirt the field, making towards the coast at Orford, the only sound that of a farm dog barking. Below this field is a large, solitary house which features in the UFO story. Light from an unknown source catches the windows at such an angle that they blaze orange. It looks like the house in The Amityville Horror.

After safely navigating the vegetable field, we next find ourselves in a field of wheat. By this time my hay fever, which has been aggravated by the forest all day, is in full spate. Through swollen eyes I do my best to look for significant lights in the sky. It is extremely hot, partly due to our attire, and we are attracting clouds of midges. We follow Rob’s dark outline towards the horizon and the direction of the lighthouse beam, which disappears and reappears from view with the undulations of the land – a faint, pulsating glow.

Rob has followed the route many times, but at the bottom of the field he plummets suddenly and alarmingly downwards into the void. There is silence and we can’t see a thing. We catch our breath, fearing he is injured, afraid to move in case we, too, fall. But he bounds out of what must be a deep ditch, unhurt and undeterred, brushes himself down and heads onward. I’m impressed at his stoicism; mine is waning at this point.

We are now approaching marshland and, authenticity aside, Rob, possibly as a result of his recent accident, decides we should make a slight detour to avoid getting wet. On we plod towards the horizon, through hedges, ditches and more fields. I begin to think we will soon stumble onto the beach, parched and bedraggled. After what feels like hours, but has actually only been around 90 minutes, we arrive at the foot of Burrow Hill, a muddy Anglo Saxon burial mound in the process of being excavated. Its summit was where the airmen ended their quest. It is midnight, and I feel a tad disappointed. I have experienced nothing akin to a Close Encounter of the Third Kind and have to confess to thinking about more earthly matters – such as a hot bath and comfortable bed. But Rob is already half way up the mound. At this point Dave digs in his heels and tells Rob we’re calling it a day – or night. I’m hugely relieved. Rob looks slightly crestfallen.

We take the most direct route back, along the Capel St Andrew Road. Half way along, I turn and catch the best glimpse of the lighthouse yet. Through a clearing in the forest it glows largest and brightest of all – a dazzling, white sphere that looks almost supernatural.

And, in spite of his scientifically researched conclusions about the Rendlesham mystery, Rob admits he can find no explanation for the blue flashing lights, or the “beam of light” that was said to come down from the sky.

Back at our B&B in the village of Eyke, on the edge of the forest, proprietor Jan Warnock, a local resident of 40 years, confides the next morning that people round there “see strange things all the time”. She claims to have once seen her own UFO after entertaining the vicar for dinner – an “enormous, white, pulsating light.”

“Once you’ve seen something like that, it’s terrifying. You never feel safe again,” she confides. Husband Tony, meanwhile, speaks of red and green lights that “veer off” at 90-degree angles.

“We don’t have technology like that,” he adds conclusively.

EXTRA INFO ON THE UFO TRAIL

The Forestry Commission received £2,000 from the Lottery’s Award for All scheme to create a waymarked UFO trail through Rendlesham Forest tracing the US airmen’s path.

The three-mile (4.8km) route starts at Rendlesham Forest Centre. The first marked site is East Gate, RAF Woodbridge.

The trail then heads east into the forest in the direction of the lights. Site 2 is at the edge of the forest at a junction with a road from the forest’s main entrance. It was here that one of the search party remained to try and maintain radio contact with the base.

Site 3 at a clearing towards the eastern edge of the forest, was where the patrol reported sighting a conical object the size of a car, floating on beams of light 12 in (30cm) above the ground. A metallic disc has been placed here.

The next day, air force personnel searched the area and found broken treetops and three small triangular depressions in the ground.

The following night, airmen were prepared for further sightings with Geiger counters, arc lighting and recording equipment. That night, at Site 4, near the point where the forest ends and farmland stretches to the coast, a pillar of yellowish mist was spotted. Then a craft was reported to have manœuvred to Site 5, back towards the heart of the forest. It had pulsating red and blue lights. The patrolmen pursued it and said it transformed into a pyramid shape. After an hour’s chase, the craft shot skywards, detaching pieces as it went.

This is the last marked site on the UFO trail, which ends back at Rendlesham Forest centre. There are plans to add interpretations to the sites in the future, but in the meantime a colour leaflet explaining the route and the story is available.