LUAS promises a fast, reliable and frequent service linking Tallaght and Dundrum with the city centre. Each tram will carry up to 200 passengers - most of them, admittedly, standing - and the service will run at six minute intervals during peak periods and 15 minute intervals offpeak.
The trams are expected to carry over 20 million passengers each year, diverting almost 3,000 car users to public transport. The journey from Tallaght to the city centre will take 38 minutes, while the shorter run from Dundrum will be just 22 minutes - less than half of what it would take by car in peakhour traffic.
The Tallaght terminus will be located between The Square shopping centre and South Dublin County Council's Civic Offices. From there, the tram will swing around by the regional hospital and through Cookstown Industrial Estate.
Crossing Belgard Road, it will travel along Treepark Road and along the edge of the M50 motorway to the Naas Road. Here there will be a new bridge.
There will be an LRT depot and "park and ride" facility to the west of the roundabout, allowing for the possibility of a future spur to serve Clondalkin. The Tallaght tram will continue its journey into town on the central median of the Naas Road towards Bluebell and Inchicore.
It will turn right at the Black Lion pub onto Emmet Road and on through the Bulfin estate, up to the top of Mount Brown into James's Street, before turning left into Steevens' Lane and down past Heuston Station.
The tram will cross the Liffey via the old Kingsbridge, turning east along Benburb Street, where there will be a station to serve the new National Museum at Collins Barracks, before crossing Blackhall Place and on into Smithfield.
The tram would then make its way towards the city centre via a busway reservation south of Irish Distillers and past the Bridewell.
Chancery Street would no longer function as a thoroughfare, with traffic limited to "access only". The same would apply to Mary's Abbey and Upper Abbey Street.
From Middle Abbey Street, the LRT lines serving both Tallaght and Dundrum would use either side of a widened central median with the station in between. The lines also cross O'Connell Bridge, again in the centre, continuing along Westmoreland Street, where there would be a station right outside the proposed Hilton Hotel.
From there, the two lines would carry on in tandem, shaving the edge (and some of the trees) off the traffic island in College Street to sweep around Trinity College into Grafton Street.
It had been thought that Trinity's railings would have to be set back to accommodate LRT on Nassau Street, but such radical surgery will not now be necessary. However, the trams will take over the short stretch linking Grafton Street with Dawson Street so that it and Suffolk Street will cease to be through routes for motor traffic.
Dawson Street will also be dramatically transformed, with LRT leaving only enough space for a single motor lane, running south towards St Stephen's Green.
In St Stephen's Green, the Dundrum line would swing out from the top of Dawson Street to the park side of the Green, taking away part of the footpath but apparently preserving its fringe of lime trees. Then the tram runs up the east side of Harcourt Street, reducing it to two lanes, and turns left into Peter Place, skirting some corporation houses.
Instead of going straight through the Charlemont Place site, now being developed after more than 20 years of dereliction, the LRT line rather awkwardly loops around the edge of it before rising up to cross the Grand Canal via a new bridge (incorporating a station) which is being designed in consultation with the Office of Public Works.
From there, the Dundrum tram will run on the embankment of the old Harcourt Street railway line: the suggestion of demolishing it to provide for street level operation has been scrapped for practical reasons.
New bridges will be needed at Dartmouth Road and Northbrook Road. The edges of the embankment are to be screened with vegetation, to minimise overlooking into adjoining back gardens. In Ranelagh, the main station will be located on another new bridge, retaining the arched entry into the nearby public park.
After crossing Chelmsford Road, the LRT route will ramp down to street level at Dunville Avenue.
It will continue along the old Harcourt Street line, crossing Cowper Road, where there will also be a new station, and onwards to Dundrum via the Nine Arches bridge over the Dodder. Here a cycleway may be provided.
A major new bridge will be required to cross the very busy traffic junction at the entrance to Dundrum. The CIE design team favours a dramatic cable stay structure. Its construction would not interfere with traffic.
Dundrum trams would terminate at Balally, opposite the Crazy Prices supermarket on Sandyford Road, where there would be a "park and ride" facility.
An additional £15 million would be needed to take it to Sandyford Industrial Estate. But there is not enough cash in the kitty for that.