Prime Minister Narendra Modi on Sunday laid the foundation of the much-awaited Patna Metro Rail through video conferencing from Begusarai in Bihar.Modi also opened the city's gas distribution at Patna and the Patna River Front Development's first phase.The Prime Minister then launched the expansion work of Barauni's oil refinery which would be increased to 9 million tonnes and other projects estimated to cost Rs 33,000 crore.The Patna Metro Rail project will cost about Rs 13,365.77 crore. It comprises two corridors of a total length 31.39 km.In the first phase, a 33.1-km-long track having two corridors -- east-west and north-south -- will come up in Patna.The west-east corridor would run between Danapur and Patna railway station via Dakbungalow Square while the south-north corridor would run between the Inter-State Bus Terminal and Gandhi Maidan via Rajendra Nagar and Ashok Rajpath.The project is expected to be completed in five years from the date of commencement.Earlier, Modi flew into Patna and was welcomed by Governor Lalji Tandon and Chief Minister Nitish Kumar. All of them then took a helicopter to Begusarai, 130 km from Patna.