A £26m package of investment in the worn-out Isle of Wight railway line has been unveiled by the government.
The Island Line service between Ryde and Shanklin currently uses 1938-built former London Underground trains.
The plans include replacing the trains with more modern Tube trains from London Underground's District Line.
A passing loop will also be created at Brading which will allow trains to run half-hourly to Ryde pier to connect with ferry services to Portsmouth.
South Western Railway said the first of the five two-car District Line trains was due to be tested on the line from early next summer.
Track improvement works will follow during the winter.
The upgrades are being paid for by the Department for Transport, with £1m for the passing loop coming jointly from Isle of Wight Council and Solent Local Enterprise Partnership.
Island Conservative MP Bob Seely said: "This is really great news for the island and long over-due.
"This represents the first significant upgrade to the route for over 50 years - since electrification in 1967."
The announcement came as Island Line said it would cut its service because one of the 80-year-old trains needed repairs.
From Wednesday it will run one train hourly instead of two.
The line runs 8.5 miles (13.7 km) from Shanklin to Ryde Pier Head, where it connects with passenger ferries to Portsmouth Harbour.
It also connects with the Isle of Wight Steam Railway at Smallbrook Junction and has additional stops in Brading, Sandown and Lake.
The railway uses London Underground trains because of the height of Ryde tunnel.
Paul Clifton - BBC South transport correspondent
It is good news for the country's most run-down railway service.
But there is no hiding from this being the simplest, cheapest, least imaginative option.
However, it is also deliverable. Big ideas for modernisation have come and gone.
Only three years ago the island's council backed a plan to convert the line into a tramway.