The quickest and easiest way to get to Lang Co is via a taxi from the Da Nang International Airport. Most taxis are metered and will cost approximately 450,000 VND inclusive of tolls and airport exit fees. Or private car service from Da Nang.
The taxi driver will always go through the tunnel, if left to his own devices, but for a more interesting ride which should only cost a further 150,000 VND, ask the driver to take the Hai Van Pass. The Hai Van Pass route will take about 50 minutes from the airport to Lang Co, while the tunnel route will take approximately 35 minutes.
There are no buses from the Da Nang international airport. To take a bus would require taking a taxi from the airport to the bus terminal for approximately 50,000 VND and then taking the bus from the terminal to Lang Co at a cost of 15,000 VND. These buses generally wait until they are full and the temperature inside can get very hot.
According to VietKings (Kyluc.vn)