Work has started on a 45 million pound project to double a twelve mile length of track between Swindon and Kemble stations.
There has been just a single railtrack between the two stations since the late 1960s, when one of the tracks was removed to save money.
Network rail says the work should be finished by march and will mean up to four trains per hour will be able to run in each direction.
More top news
Another sparkling start with lots of sunshine and barely a cloud in the sky, temperatures feeling very warm but high UV levels too.
Long sunny spells and warm temperatures ahead for the West today, but also high UV levels.
Extra spending on the NHS, cutting net migration and adding grammar schools to every town were just some of UKIP's manifesto pledges.