A newly developed nano-structural material, zeolite-templated carbon (ZTC), adsorbs a large amount of water, up to 120-170 wt.% with respect to the dry ZTC. Here, we investigated this nanoconfined water by several experimental methods, including specific heat and nuclear magnetic resonance measurements, and molecular dynamics simulations. The water was highly mobile down to 200 K and its rotational correlation time followed an apparent non-Arrhenius behavior. With decreasing temperature, it was suggested that the water freezes into a low-density amorphous ice with a possible glass transition temperature of around 150 K. ZTC provides a new platform to study three-dimensional 'supercooled' water. (C) 2013 Elsevier B.V. All rights reserved.