The public are being invited by the Rail Procurement Agency (RPA) to add their voices to the debate on the proposed link between the two Luas lines.
Plans of the five proposed routes through Dublin City centre have gone on display in the Fitzwilliam Hotel in St Stephen's Green as part of an open day to allow the public view the options.
A RPA spokesman told ireland.comthe open day was essentially an invitation to the public to look "in more detail" at the proposed routes.
He said engineers and transport planners will be there to explain the implications of the various options.
Suggested routes from St Stephen's Green include lines along Dawson Street and Nassau Street, a line serving Merrion Square and Pearse Street, and a route running along South King Street and South Great George's Street to Dame Street.
The board of the RPA will ultimately sign off on an option that will form the basis of a railway order application, which will eventually go before Minister for Transport Martin Cullen for approval.