The Matterhorn Gotthard Bahn railway company said the first shuttle trains between Zermatt and Täsch began operating at 17:15 (16:15 GMT) on Wednesday.
Thirteen thousand tourists are now stranded in a Swiss ski resort following heavy snowfall, increasing the risk of avalanches.
Thousands of tourists have been left stranded in the Alps after heavy snowfall.
The stranded tourists will not be able to ski for the time being, due to the high risk of avalanches.
It said teams were working "as a matter of urgency" to try to open roads to Zermatt.
The rail network in Tasch remains closed due to snow, but replacement buses are operating, making it possible for people to reach regional airports.
The ski village and others at high altitude in Switzerland's Valais region have received more than three feet of snow in recent days, forcing the avalanche risk to be raised to its maximum level, according to the region's president, Romy Biner-Hauser.
The tourism office's website noted a "power breakdown all over Zermatt" and requested people stay at home so not to disrupt those clearing snow.
He said the helicopter journey costs "around 200 Swiss francs ($204, 170 euros) per person" and stressed that the flights should not be described as an evacuation.
The unusually heavy snowfall has caused havoc across the Alpine region, and led to several casualties.
One skier was killed and another injured during an avalanche in the French Pyrenees.
British snowboarder John Bromell, of Lincolnshire, is still missing after he was last seen heading to the slopes in the French ski resort of Tignes on Sunday.
The main access road has been closed since early Monday, while the train was halted Monday evening, she said. The only way out previously was via helicopter with around 100 people airlifted out every hour.