A recent theoretical study by Fujie Tang and colleagues has delved into the realm of water wires, linear structures of more strongly hydrogen-bonded water molecules, which have been elusive in direct observations. Through rigorous electronic-structure calculations and molecular-dynamics simulations, the researchers propose a method to detect water wires in bulk water and ice by analyzing light absorption in the UV-to-visible range. The study sheds light on how water wires facilitate proton transfer, impacting electrical conduction in ice, acid–base chemistry in water, and biological processes. By combining simulations and calculations, the researchers identify a spectroscopic fingerprint of water wires in the UV absorption spectrum, linked to collective excitations and charge-transfer excitons. The computational techniques utilized in the study, including artificial intelligence to enhance quantum simulations, provide accurate descriptions of light–matter interactions in hydrogen-bonded systems. The results show that the intensity of the spectroscopic peak is highest in proton-ordered ice, where water wires are stable and extended, and weakest in liquid water, where the wires dynamically form and break. Future experiments could focus on monitoring spectral features to understand the behavior of water wires under different conditions, offering insights into proton transfer mechanisms in various chemical and biological processes.