MILAN (AP) -- Workers will begin drilling and blasting open the first tunnel connecting Austria to Italy under the Brenner Pass through the Alps on Thursday, marking a major milestone in a series of ambitious European Union projects that will accelerate passenger train travel between metropolitan centers and shift freight off the roads and onto rails.

The Brenner Base Tunnel, which is being billed as the longest underground rail tunnel in the world when completed, is among four key infrastructure projects that promise to reshape how Italians travel and ship goods by the early 2030s.

Tunnels will cut travel times between Verona and Munich by 40% to three hours, between Milan and Paris by at least 30% to 4½ hours and put the Ligurian port city of Genoa within commuting distance of Italy's finance and fashion capital -- significantly remaking the Europe transit map.

The boldest and most contested projects of them all, the recently approved Straits of Messina Bridge, will finally link the Italian mainland with Sicily -- a project first envisioned by the ancient Romans and long delayed by modern Italians.

The tunnels and bridge will mark the first significant upgrade to the Italian rail system since the Rome-Milan high-speed rail line was launched in 2008. It drastically reduced travel time between Italy's financial and political centers, effectively killing the once-lucrative Rome-Milan airline route. The rail line can now be traveled in as little as three hours.

The current projects also aim to reduce truck traffic on highways -- with the biggest impact expected on the Brenner Pass, which is traversed by more than 2.5 million trucks annually, making it one of Europe's busiest Alpine routes and a crucial north-south link, bringing Italian automotive components and small machinery northward. The Brenner Base Tunnel aims to shift up to half the heavy road traffic to rail.

While pursuing these major projects, Italy's rail network has another 40 strategic projects in the works, many funded with 25 billion euros (nearly $30 billion) in European Union pandemic recovery funds. They include a high-speed line between Naples and Bari on the heel of the Italian boot.

These are the four major infrastructure projects:

The Brenner Base tunnel, which will be the longest underground rail tunnel in the world, will run for 55 kilometers (34 miles) between Tulfes, Austria, and Fortezza, Italy, extending to 64 kilometers (nearly 40 miles) with existing tunnels from Tulfes to Innsbruck.

The project, which is estimated to cost about 8.8 billion euros (nearly $10.5 billion), is expected to be completed by 2031 with the first train traversing it in 2032. The project, launched in 2014, is being co-funded by Italy, Austria and the EU.

A 53-kilometer (33-mile) high-speed rail line connecting the port city of Genoa with Tortona in Piedmont, with links to Milan, includes 37 kilometers (23 kilometers) of tunnels.

One of them is 27 kilometers (more than 16½ miles) long. It aims to shift the transport of goods from the Ligurian port cities of Genoa, La Spezia and Savona to northern Europe from road to rail beginning next year, increasing to 50% by 2050.

Passenger train travel time between Milan and Genoa will be cut to about an hour from more than 1½ hours. The cost is 8.5 billion euros ($10 billion) and the tunnels are 90% complete. Started in 2012, the project was slowed by the difficult geology of the Apennine range, including the discovery of natural asbestos.

The 11-billion-euro ($13 billion) Lyon-Turin High-Speed Rail Tunnel extends more than 65 kilometers (40 miles) with 57½ kilometers (nearly 36 miles) of the Mont Cenis base tunnel running underground from Saint-Jean-de-Maurienne, France and Susa, Italy.

It's expected to be completed around 2033. The project aims to remove more than 1 million heavy goods vehicles from roads in the western Alps between France and Italy. Passenger travel time between Paris, Europe's second-largest metropolitan area, and Milan, Europe's third-largest metropolitan area, will be reduced to 4½ hours from 6½-7½ hours.

The project, launched in 2007, was slowed significantly by environmental protests on the Italian side. It's being co-funded by France, Italy and the EU.

The 13.5 billion-euro ($16 billion) Strait of Messina Bridge project will speed travel between the Italian mainland and Sicily and incorporate rail connections to Palermo and Catania, which are being upgraded.

The single-span bridge itself will span from Messina, Sicily, to Villa San Giovanni, Calabria, with six car lanes and two rail lines. The government is awaiting final approval by the court of audits to launch preliminary work. It's expected to be completed by 2032.