This is a strange land of marshes and creeks, sea frets and mud flats, a land once plagued by demons whose ghostly lights haunted this other-worldly corner of Suffolk.

The church of St Botolph is one of around 60 which bear the saint's name and is one of Suffolk's hidden gems, a thatched church built on a bluff above the River Alde where the Saxon nobleman Botolph landed and was gifted land on which to build a monastery. It was here that Botolph set about 'exorcising' the swamps of the "devils" that glowed in the night and filled those that lived close by with fear at what lay in waiting on the marshes.

Botolph and his brother Adolph lived in the seventh century and were sent away to be taught at a Benedictine Abbey in France - Adolph became a Dutch Bishop while Botolph returned to East Anglia to build his house of worship...and banish demons. To introduce a somewhat unwelcome hint of science to a story of wonder and magic, it is likely that Botolph's enchantment of the marsh demons was, in fact, due to his draining of the land which eliminated the marsh gas and the luminescence known in other parts of the country as Will o' the Wisps.

In 1799, Samuel Taylor Coleridge had written about the Lantern Man, or Will o' the Wisp as many called the ghostly lights that hover and wheel above boggy marshland on dark, moonless nights, in 'The Rime of the Ancient Mariner'.

"About, about in reel and rout, the death-fires danced at night; the water, like a witch's oil, burnt green and blue and white." Coleridge's "death-fires" were first mentioned in print in 1563, described as ignis fatuus: "foolish fire that hurteth not but only feareth fooles." Forty years later, Shakespeare wrote of "wild fire" in Henry VI Part I, while Will o' the Wisp was first mentioned by the dramatist John Day in the early 1600s. Sir Isaac Newton wrote of the eerie marsh light in his opus Optick, published in 1704. Popular tradition said Will, the Lantern Man or Jack o' Lantern, carried candle-lit lanterns in the darkness to attract weary travellers, who they would lead across the marshes to their certain death.

Back in Iken, Theo Clarke's Ebb and Flow: River Heritage Walks of 2008, suggests that Botolph had more than marsh demons to contend with: it says there were unexplained deaths during building work, ghosts were reported and building materials were moved mysteriously at night. On the Griffmonster Walks website it reads: "Icanho [Iken] was indeed an island in the Alde estuary surrounded by marshes and was considered a gloomy and evil place haunted by ghosts and marsh demons. "Botolph initially attempted to build his monastery on Yarn Hill but during the night the stones would be moved and the workers were found dead, their bodies mutilated.

"The road to Scillasforda (Chillesford) was also said to be plagued by ghosts of restless souls. Botolph believed the island was possessed by the devil himself and built the Iken High Cross, a monolith of stone seven feet tall and inscribed with carvings of wild dogs and wolves.

"This was to ward off the evil spirits and banish the devil from the island. This appeared to work and the construction was shifted from Yarn Hill and on to where the modern day church stands." The lower part of a cross was found by Dr Stanley West in 1977, built into the base of the tower of Iken church and believed to be a memorial to St Botolph, carved many years after his death, possibly a copy of another cross made earlier.

St Botolph died after a long life of Christian endeavour in 680 and his monastery continued for another 200 years until it was destroyed by Danish invaders in 870AD. His remains were buried at another place said to have been haunted by marsh demons, Burgh, north to the present parish of Grundisburgh, and then around 50 years later, King Cnut granted permission for his relics to be divided between churches including Bury St Edmunds, Ely, Thorney and possibly Hadstock. It is perhaps this last journey, after his last breath, that led to St Botolph becoming the patron saint of wayfarers and travellers or maybe he is remembered for banishing the demons that lit their cold fires on the marshes to lure travellers to their deaths.