A £15m project to improve reliability on Cornwall's main rail line is officially opened on Tuesday.
The 7.5-mile (12km) length of track was reduced to a single line in 1985 and since then has caused regular problems.
Now the route between Probus and Burngullow has been restored to two tracks.
Objective One funding, which gives European cash to low-income areas, is providing £3m and the Strategic Rail Authority is putting in £12m.
The county's tourist and business industries are likely to benefit from the increased punctuality, as trains travelling in different directions will no longer have to wait for each other .