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.
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Highs this afternoon of around 23 or 24 degrees. Cooler on the coast.
It's warming up! Highs of around 23 or 24 degrees this afternoon.
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