Ticket Pricing between Drogheda and Dun Laoghaire

[coffeedrinker]

I normally buy a weekly ticket from Drogheda to Dun Laoghaire. However, one morning over Christmas there was no-one selling tickets in Drogheda station so I said I would buy my ticket in Dun Laoghaire. When I went to purchase the same ticket I usually buy in Dun Laoghaire I had to pay an extra €10.50 for the week - why??

I argued and was told that was the price of it end of story! After a few phone calls, I was told that the journey from Drogheda to DL and the journey from DL to Drogheda is not the same - hence the price difference! I was then told that Drogheda are selling illegal tickets by charging the lower price! I was also told that the computers in both stations would have been programmed differently.

What is the actual reason behind this price difference? And what is the correct price of a weekly ticket for this journey????