Explore the groundbreaking field of gravitational wave astronomy in this 1-hour 7-minute lecture by Rana Adhikari at the International Centre for Theoretical Sciences. Delve into the detection of gravitational waves predicted by Einstein, and learn how the LIGO project uses ultra-sensitive laser interferometers to measure spacetime distortions from black hole collisions billions of years ago. Discover the challenges of measuring motions smaller than a proton, the evolution of gravitational wave detectors, and the future of LIGO, including the LIGO-India project. Gain insights into cosmic time, dark matter, black holes, and the workings of interferometers. The lecture concludes with a Q&A session, offering a comprehensive overview of this cutting-edge area of physics and cosmology.