South Dublin residents are calling for the final stop of the long-awaited MetroLink to be relocated from Charlemont to Cathal Brugha Barracks.
The MetroLInk is a planned underground rail transport network that will run from Dublin Airport to the city centre.
The plans for the rail system have been dogged by controversies with the first promises for the infrastructure project being made in 2000.
Over 1,000 people living in the area have said the proposed terminus in the Portobello area is "simply wrong".
Last year, the MetroLink project was postponed for another 10 years.
A draft strategy published by the National Transport Authority (NTA) shows that work on the proposed underground train line linking the city to Dublin Airport - itself already scaled back massively from initial plans - will now not get going until 2031 at the earliest.
The proposed final stop at Charlemont would also encompass a stop at Darthmouth Square on the other side of the canal.
In a letter to Transport Minister Eamon Ryan, the angered residents said: "There is a fundamental flaw in the proposed South Terminus of MetroLink that will reduce the utility and future value of the overall metro system – it is simply in the wrong location. This view is fully supported by numerous community groups across the southside."
They say the Chrlemont site will not allow for proper integration with other forms of transport such as cars - due to a lack of access - and a direct bus route.
And that developing the terminus in Charlemont is a "waste of money" because of the complex problems it presents in a "cramped" site.
The residents argued that the Cathal Brugha Barracks, which Minister Ryan recently said would be a good site for a huge housing project, would allow for a shift towards sustainable public transport.
They wrote: "A future connection to Cathal Brugha Barracks (or its selection as the south terminus of MetroLink) would provide a golden opportunity to directly service 1,000 homes and showcase a "modal shift" towards sustainable public transport in which there is full integration with the future transport fleet of zero emissions vehicles, cyclists and walkers."
In conclusions, the residents urged Minister Ryan to change the "fundamentally flawed" planned MetroLink.
They said: "We believe that the current MetroLink proposal is fundamentally flawed in misplacing a south terminus at Charlemont and we urge you, as Minister for Transport, to avert a major mistake that could cost hundreds of millions of euros and deliver a compromised metro system."
Dublin Live has contacted the Department of Transport for a comment.
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