  Observing matter effects in atmospheric neutrinos travelling through the
entire mantle and core of the Earth is a promising way of enhancing our
understanding of Earth's density structure. In that context we study the
prospects of Earth tomography with the ICAL detector at the India-based
Neutrino Observatory. While this experiment is smaller in size in comparison to
some of the other bigger detectors being proposed, it is the only neutrino
experiment with charge-identification sensitivity. In particular, ICAL can see
matter effects separately in neutrinos and antineutrinos. This has been seen to
enhance ICAL's sensitivity to earth matter effects and hence the mass ordering
sensitivity for both normal and inverted mass orderings. It is therefore,
pertinent to see if the ICAL sensitivity to earth tomography is competitive or
better with respect to other experiments, especially for the inverted mass
ordering, where other experiments suffer reduced sensitivity. We present the
sensitivity of ICAL to earth tomography by taking into consideration both the
Earth's mass constraint as well as the hydrostatic equilibrium constraints.
