Lidar survey (Light Detection and Ranging Survey) is a survey conducted using laser data, GPS data and photographic data. The National High Speed Rail Corporation Limited is to be using this technique to prepare for the Delhi to Varanasi High Speed rail Corridor. Laser-enabled equipment are to be mounted on helicopter and the ground is to be surveyed aerially to yield accurate data. The data is to be used to determine land requirement, location of stations, structures, alignments, etc.