Fifteen years ago, the University of Victoria’s Ocean Networks Canada made history as the world’s first large-scale, interactive, real-time portal into the ocean. On 8 February 2006, a large underwater telecommunications power bar—known as a node—was lowered to the bottom of Saanich Inlet’s coastal fjord off Vancouver Island, enabling a flow of continuous, real-time data to the surface for science, society and industry. Throughout 2021, we will be celebrating our 15th anniversary with events, talks, stories and activities highlighting fifteen years of ocean observing, featuring the innovative science, data and collaborations made possible by listening to the heartbeat of the planet.