Currently linked only by ferry, the project aims to bring Helsinki and Tallinn together into a single metropolitan area.
An undersea train tunnel between Finland and Estonia is a step closer to becoming a reality, with a protocol of intent to build set to be signed by both countries on April 26.
At 103 kilometres long - twice the length of the Channel Tunnel - it will stretch under the Gulf of Finland to connect the airports in both capitals, Helsinki and Tallinn, with two train stations in between.
Currently linked only by ferry, the project aims to bring the two cities together into a single metropolitan area.
It's hoped the tunnel, which could be ready by December 2024, will provide economic growth for the countries.
Peter Vesterbacka, founder and executive chairman of the FinEst Bay Area Development who is spearheading the project, told Euronews the idea will bring growth to the area.
"We are building four station areas and those will accommodate 50,000 people living, working, and studying in each one," he said
"This is all part of the FinEst Bay Area Development, attracting more startup entrepreneurs from all over the planet to come here to Helsinki and Tallinn. They'll be the next big thing."
The project is privately funded and Vesterbacka said building the physical tunnel will take roughly two years.
"We're going to use 60 tunnel boring machines," he added. "This plasma drilling technology allows us to go even faster.
"Of course, then doing it as a private project allows us to move much faster ... we don't need to do all the public procurement processes and all of that. So that actually reduces the construction time significantly."
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