Water is important in many scientific and technological areas, yet our understanding of this remarkable liquid remains very incomplete. In may cases, it is the properties of water at a surface or interface, rather than in the bulk, that are the key to the system's overall behaviour. There are many diverse examples where this is the case, ranging from protein folding to the uptake of water by soils. In this experiment, we will use the unique powers of neutron scattering to measure the structure of water in a particular type of clay mineral, known as halloysite. Halloysite is remarkable in this context, because it occurs as nano-scale tubes, which are formed from rolled-up scrolls of the clay sheets (like a swiss-roll, where a single molecular layer of water is the jam, and the clay sheet is the sponge-cake). Our expeirments will allow us to study water structure under extreme confinement.