After leaving Rovio in the summer of 2016, Peter Vesterbacka has been involved in countless new projects, among them the creation of a rail link between the Finnish and Estonian capitals.
Drawing on financing and technology from China, he says that construction could start next year.
"Technically, it's no problem. It can be built in five years. We are talking about a tunnel that would be completed in the 2020s and not the 2030s," Vesterbacka told Hufvudstadsblad.
"We have not yet encountered any insurmountable problems," he added.
Twelve tunnel drilling machines for the project are estimated to cost 30 million euros. Vesterbacka has a vision of creating what he calls a sort of "tunnel factory" that the rest of Europe and the world could turn to for other projects. His plan is for the equipment is to be contracted from China.
"China is implementing major infrastructure initiatives throughout the world, so it's no wonder that they're interested in constriction here, too," he points out.
In order to hit a five-year deadline for completion, work on two parallel tunnels would be carried out at six sites simultaneously. Under this plan, each of the tunnels would be 17 meters in diameter.
"It's bigger than needed, but it will be made for any future needs," he explained to the paper.
The project being promoted by Vesterbacka includes four stations: one in Tallinn, one on an artificial island to be built just off the coast of Helsinki, one at Keilalahti-Otaniemi in eastern Espoo, and one at Helsinki-Vantaa Airport.
"With the tunnel, we want to show that Finland is not an island, but that we are connected to Europe. Looking in the other direction, Helsinki Airport becomes a hub for residents of Tallinn. It is important to have a connection to the airport."
Vesterbacka believes that interest in car traffic in the future will decrease and so no car tunnel is planned.
To Tallinn in 20 minutes for 50 euros
This tunnel project is estimated to cost 15 billion euros. Vesterbacka says he is not looking for tax money.
"It's a completely private project, we are not looking for money from the state or the EU. We are trying to optimize everything in order to be as fast as possible, which is also a way to save money."
According to Vesterbacka, with ticket prices averaging 50 euros, the tunnel would pay for itself within 37 years. The travel time between the two capitals would be around 20 minutes.
"The line would be operated by high-speed trains running at 350 kilometers per hour. The technology already exists in China and Japan, so it is no technological risk," he says.
Vesterbacka conceded that no funding is certain until the papers have been signed. He says, however, that attitudes toward the project have become significantly more positive over the past year.