The Chandigarh-Manali National Highway 21, which was closed for vehicles near Patlikuhl, 20 km before Manali, was reopened, officials said, but vehicular movement beyond Dhalli, 10 km from here, remained suspended since a large stretch of the Hindustan-Tibet Road was under a thick blanket of snow.
The entire Kinnaur district and towns in Shimla district such as Narkanda, Jubbal, Kotkhai, Kumarsain, Kharapathar, Rohru and Chopal have been cut off from the rest of the state, a government official said.
"The road link to towns in upper Shimla is likely to be restored within a day or two," Shimla Deputy Commissioner Dinesh Malhotra told sources.
Officials said the road network in the higher reaches of Kinnaur, Shimla, Chamba, Mandi, Kullu and Sirmaur districts was worst affected and efforts were being made to reopen it.
Buses from Shimla town to Rampur were plying via Mashobra.
The internal roads in the tourist resorts of Shimla and Manali were too slippery for traffic as these were laden with snow. Even walking in the streets was risky.
Although the Shimla Municipal Corporation has cleared the snow on Cart Road and some VIP roads, most of the other roads have not been cleared yet.
Due to slippery condition of roads and pathways in Shimla, more than 10 people, most of them tourists, were injured, police said.
Lahaul-Spiti Deputy Commissioner B.S. Thakur said three avalanches occurred in the district but there was no loss of life and property.
A high alert has been declared in higher reaches mainly in Kinnaur, Lahaul-Spiti and Pangi subdivision of Chamba which experienced heavy snowfall.
According to the Met office here, Shimla recorded 13.7 cm of snow in the past 24 hours and it recorded a low of 0.6 degree below freezing point.
Manali, which saw 15 cm snow, recorded a low of minus 3.6 degrees Celsius while the temperature was 3.8 degrees in Dharamsala.
The Met Office has forecast mainly dry weather across the state in the next few days.