Supporters of an underground connection between Boston's two main rail hubs are continuing to make their case on Beacon Hill.
On Monday, members of the North South Rail Link Working Group are planning to host leading world experts on urban rail link projects at a Statehouse forum.
Monday's discussion will focus on the latest tunnel-boring technology that backers of the rail link say has helped reduce the cost, risk and disruption of urban tunnel projects.
The working group includes former Democratic Gov. Michael Dukakis and Republican Gov. William Weld.
Democratic Congressman Seth Moulton has said the rail link makes sense and would not resemble the Big Dig.
Republican Gov. Charlie Baker has expressed skepticism about the project. He is focused instead on a plan to expand South Station.