Clancan was once the territory of the McCann sept and now roughly corresponds with the civil Parish of Tartaraghan.

The territory between the Rivers Bann and Blackwater, immediately south of Lough Neagh, and known as Clancan, must have been very sparsely populated in medieval times as much of it was covered by forest; this is indicated by the number of townlands whose names are prefixed by the term "Derry", signifying an oak grove or wood. A large tract of land was only slightly above the level of the Lough, and consequently was marshy and subject to frequent flooding. Sir William Petty map, "Hiberniae Delineato" published in 1685 has a blank space between Drumcree and Magheregreen (Maghery), which would indicate that this territory was either not surveyed at that time or contained nothing note-worthy.

The most interesting piece of antiquity, however, was the remains of an old road which was called St Patrick's Road. At the time of the first Ordnance Survey (1837) it could be traced from Lough Neagh towards Armagh, passing through the townlands of Derrylileagh and Derrycorr. Tradition says that it was used to bring sand from the Lough for the building of the Cathedral in Armagh. Be that as it may, those who saw it in the 1830s were convinced that it was a very ancient road, and that much care and labour had been bestowed on its construction. The road, where it traverses soft areas of bogland, was composed of large planks of oak laid length-wise on top of which were yew planks laid at right-angles (ie with the cut ends to the outside). This was covered with clay and the whole surfaced with paving-stones. The road was discovered in places well below the surface of the bog, being exposed during turf-cutting operations at a depth of about 1.5 metres. Incidentally, in this area several interesting finds have been made: in 1815 a gold gorget was dug up in the Derrycorr bog, it weighed 12oz and was richly chased. A bronze sword was uncovered in the Derrylileagh bog, and a few arrow heads were also found.

During the 17th century travel throughout Clancan was frequently fraught with difficulties and dangers for the unwary. In 1650, following the hoisting of Cromwell's Standard on Charlemont Fort, Sir Charles Coote, one of Cromwell's Generals, despatched a party of horse into this area to carry out mopping-up operations. On the 30th November of that year, a troop of horse consisting of four officers and seventy men passed into the woods and bogs of Clancan, but were there routed by little more than a dozen of McCann's men. In their panic they fled headlong into Annagarriff bog where both men and horses perished. Charles Roe, who some years later recorded this incident says, "We marcht to the myre of Annagarfe and saw the yellow jerkins (jackets) of our army in the hell-deepe mud.

As the old forests were gradually cleared in the 18th century there was a steady influx of settlers into the district. Tracks and roads developed until, towards the close of the following century, they comprised an intricate network, by which time, what was then known as the Tartaraghan Rural District, was the most densely populated Rural District in Ireland. Rocque's map of County Armagh (circa 1760) shows that the main road from Portadown to Dungannon ran through the district by way of Richmount, "Clock Hill" and Verner's Bridge. The steep gradient of the Cockhill presented a formidable obstacle to any horse drawing a laden cart, and the help of a trace-horse would have been required.

An old inscription in the garden wall opposite Clantilew House makes interesting reading:

Miles Furlongs Perches
Armagh 8 4 36
Loughall 4 3 19
Charlemont 6 0 32
Portadown by Birch Wood 6 2 00
Portadown by Cockhill 4 4 36
Verners Bridge 4 4 24
Blackwater Foot 3 5 14

The main roads through the district were maintained at the expense of the Council but the bye-roads had to be kept in order by the Parish in which they lay. For this purpose it was customary to lay a Cess or tax upon the Parish at a rate per acre determined by the Easter Vestry. The old Minute book reveals that a special Vestry meeting was held in Tartaraghan Church on September 6th 1832 "for the purpose deciding whether a sum shall be assessed on the Parish this year for the repair of the bye Roads of the Parish according to the Act of Parliament which authorizes a Cess of from One penny to Two pence per acre for that purpose ... it appears expedient to lay on as small a Cess as the Act of Parliament allows, viz. One penny per acre or Seventeen Pounds Twelve Shillings in all. The Statistical Report of 1835, under the heading of "Communications" states that the bye-roads and lanes of the Parish are numerous, the latter being for the most part very bad particularly in the townland of Drumannon.

Due to the poor condition of the bye-roads, many people living in the northern portion of the Parish experienced hardship in travelling to the Market in Portadown and it was often difficult to summon medical aid, the Tartaraghan Dispensary District stretching as far as Maghery, some seven miles from Portadown where the Medical Officer resided. In 1864 it was proposed that Dr Stewart be given an increase in salary (then £80 per annum) because of the difficult task he faced in visiting the homes of many of his patients, and it was pointed out that in a large number of cases he could neither ride nor drive to the dwellings of the sick, but had to tramp on foot over moss ramparts to the danger of his life.

As the territory of Clancan was bounded by rivers to the east and west and to the north by Lough Neagh, it is only natural that water should have formed an early form of transport, both the Bann and Blackwater being navigable for barges of up to 50 tons burden; so to facilitate passage between them a short canal, "the Maghery Cut", was made between Derrywarragh Island and the mainland. In the middle of the 19th century considerable quantities of turf were transported up the river Bann to Portadown and beyond; and towards the close of the century the Derrylard Peat Moss Industry dispatched large quantities of baled peat litter, its superior quality being described as "soft as a feather and as absorbent as a sponge". It was transported by barge to Belfast from a wharf on Lough Neagh, one single customer, the Belfast Street Tramway Company, using about 1,500 tons per annum to bed its 1,100 horses.

The opening of the Portadown and Dungannon Railway on April 5th, 1858, had a bearing on communications as it passed through the south-east corner of Tartaraghan the nearest Station being Annaghmore. Here a "Miss-adventure" occurred not long after the opening of the line. Near the Station is a public-house, then in the possession of a family named Telford. A certain engine driver, John Hardstaff, became friendly with Miss Telford but her father was determined to end the romance. However, the couple were not to be deterred and decided to elope together on the last train to Dungannon on September 9th, 1858, and of which he was the driver. Her father receiving advance knowledge of the plan, enlisted the help of the Station Porter, Mr Reilly.

They patrolled the platform but when the train arrived the girl boarded from the track on the other side of the carriage, assisted by driver John. But things went wrong, for as the rain began to pull out of the Station, Reilly realising that the girl had eluded them, quickly switched the points sending the accelerating train into a siding. It smashed through the buffers and came to an ignominious halt in the bog. Miss Telford, realising what had happened, jumped out of the carriage and found herself stuck in the mire with water up to her waist. John Hardstaff helped to extricate her, and then had some questions to answer. But perhaps it was all worthwhile, for we learn that the next day she succeeded in placing herself under John's care, on a train of which he was not the driver!

The single line track was doubled in 1899, and there were proposals that a Halt should be made at Clantilew Bridge to facilitate the locals, but this failed to materialise. Although a large amount of fruit was brought to Annaghmore Station for export, and a special store was erected about 1930, the line did not come up to expectations and was reduced to a single tract in 1936. The 1939-45 war brought a temporary revival in business, but the line was finally closed, the last train running on February 15th, 1965.

Before the end of the 19th century the bye-roads were maintained under order of the Grand Jury, the work being contracted out in many instances to local people. In 1894 the repair of the 3rd class Tartaraghan Glebe Road "between George Baxter's in Breagh and John Robinson's in Eglish", some 480 perches (2,400 metres) was undertaken by John Hyde at 4d (2p) per perch, to be coated where necessary with whin stones to a width of 5 feet.

As the century drew to a close communications were improving rapidly. About 1899 the first telegraphic connection was established between Maghery, the Birches and Portadown via Clantilew. In that year "a well appointed brake" was running each Thursday afternoon between the Imperial Hotel, Portadown and Maghery. With the dawn of the 20th century the motor car made its appearance in the district, in fact the first car to be registered in County Armagh, 'IB 1', was owned by Mr Joseph Atkinson of Summer Island, who later came to reside at Crowhill the family home. It was a 5 h.p. Locomobile, driven by steam, and registered on December 24th, 1903.

As traffic increased in volume the roads were gradually improved, but the section of main road between the Birches and Verner's Bridge, passing as it did through bogland, suffered greatly from subsidence. Along here the first section of the M1 motorway was constructed at considerable expense and opened to traffic on December 1st, 1964. Few people travelling along this section of motorway today realise that they are passing through what was at one time the no-man's-land of Clancan, which was to become for a time the most densely populated Rural District in the land.