 Built in 3807 or 3806 BC , the track was a walkway consisting mainly of planks of oak laid end @-@ to @-@ end , supported by crossed pegs of ash , oak and lime , driven into the underlying peat . The planks , which were up to 40 centimetres ( 16 in ) wide , 3 metres ( 120 in ) long and less than 5 centimetres ( 2 @.@ 0 in ) thick , were cut from trees up to 400 years old and 1 metre ( 39 in ) in diameter , felled and split using only stone axes , wooden wedges and mallets . The length , straightness , and lack of forks or branches in the pegs suggest that they were taken from coppiced woodland . Longitudinal log rails up to 6 @.@ 1 metres ( 20 ft ) long and 7 @.@ 6 centimetres ( 3 @.@ 0 in ) in diameter , made of mostly hazel and alder , were laid down and held in place with the pegs , which were driven at an angle across the rails and into the peat base of the bog . <unk> were then cut into the planks to fit the pegs , and the planks were laid along the X shapes to form the walkway . In some places a second rail was placed on top of the first one to bring the plank above it level with the rest of the walkway . Some of the planks were then stabilised with slender , vertical wooden pegs driven through holes cut near the end of the planks and into the peat , and sometimes the clay , beneath . At the southern end of the construction smaller trees were used , and the planks split across the grain to utilise the full diameter of the trunk . Fragments of other tree species including holly , willow , poplar , dogwood , ivy , birch , and apple have also been found . 
