Results from Monte Carlo calculations of the longitudinal and lateral development of the nucleon-meson cascade in iron initiated by 1- and 3-GeV protons are presented and compared with experimental results. In general, the calculated and experimental results are in good agreement, although in the 3-GeV case the calculation yields a smaller buildup of particles for the smaller penetration depths. The Monte Carlo results for the longitudinal development are also compared with available results from a calculation using the straightahead approximation, and the agreement is quite good.