Northern Ireland Plans for a tunnel between Northern Ireland and Scotland being explored A team at Heriot-Watt University in Edinburgh, Scotland is exploring the possibility of a "submerged floating tube bridge" between Northern Ireland and Scotland. IrishCentral Staff Facebook Comments Plans are reportedly being explored by a team in Edinburgh regarding a floating tunnel to link Northern Ireland and Scotland. Eoin MacDonald, a member of the team based at Heriot-Watt University in Edinburgh, told The Times: "From an engineering perspective, an SFTB [submerged floating tube bridge] as a concept is very exciting. "It is entirely feasible that this technology could be used to cross the Irish Sea.