Prior to the start of the Manx Heritage Transport Festival the railway has been supplied with quarter-mile posts along its entirety.  Prior to the complete relaying of the south line in conjunction with the all-island sewerage project I.R.I.S. few of these were still in place but there were some still in evidence.  During the 1970s when the Railway Company was back in charge of the line the Supporters' Association made and erected half-mile posts along the line and these were distinctive for their red coloured numerals, whilst the later incarnations into nationalisation times had black lettering. 

The previous posts were not placed with total accuracy and historically the markers denoting each quarter-mile wew denoted by having different shaped tops and no numbers - the one notable exception being the marker within the environs of Port Erin Station noting the 15 and three-quarter mile length of the entire line but this too has been replaced with a 15 and a half post at the buffer stops, now that accurate measurements have been taken.  It is understood that these have been installed to provide easy reference points for locomotive crews and permanent way staff, with many of the old colloquial place names falling out of use.  They have also been placed with a larger degree of accuracy so that crews will be able to time the progress of each train and monitor its speed.  The posts themselves are unpainted with caps on each post, and black letters on white backgrounds placed diagonally from the track so as to be visible when approaching them from either side.