The latest phase in a project which has suffered years of delays kicked off with only Italian and French dignitaries as well as media informed about it to avoid potential violent demonstrations.
"We have entered the drilling phase, the project is now more irreversible than ever," Turin's mayor Piero Fassino said.
The Italian and French parliaments are racing to rubber stamp the project before a summit on November 20th in Rome, amid fierce protests from locals and environmental campaigners who say it is too expensive and is unnecessary.
Europe will stump up 40 percent of the €8.5 billion needed to build the 57 kilometre long transalpine tunnel, with Italy paying out €2.9 billion and France €2.2 billion.
The first 200 metres of the reconnaissance tunnel were dug using mechanical diggers. With the tunnel boring machine excavators expect to advance between seven and ten metres a day to cover the 7,300 metres remaining.
The shaft will be used to better understand the geological make-up of the mountain range and serve as an access route while the main rail tunnel is being dug out, and in the long term as an emergency escape route and ventilation tunnel.
The high-speed Lyon-Turin line "has a triple value: European, economic and environmental," said Louis Besson, the head of the French delegation.
The link, set to come into service in 2025, is expected to see one million fewer lorries on the motorways a year, and reduce train times between Paris and Milan from seven hours to just over four.