The Playfair Project completed in 2004 joined the two historic buildings with an underground link.

The underground link is projected to place the inner city within a 30 minutes travel for around 370,000 people.

Things that happen together can have underground links.

A direct underground link with the railway station was opened in February 2011.

"Is that coming out of the underground link at Byssina?"

It will be connected to the main terminal building by an underground link.

The jail connects to the Hall of Justice by an underground link.

This idea has been dropped, but an underground link between the Casón and the Army Museum is still being discussed.

It is now nearly ready for the tunneling machines that should create, at last, an underground link between Britain and France.

An underground link between the two, to allow easier road crossing and protection from bad weather, has been planned but not built due to cost reasons.