We used receiver functions (RFs) from broad-band seismic stations to investigate the crustal structure of the Northern Apennines, Italy. Additionally, we use data obtained in this study to provide initial constraints for a map of the Moho depth of Italy. Ten stations were deployed along a transect during the 1994 GeoModAp project. RF analysis shows the presence of lateral variations in the crust. We observed patterns of symmetric and anti-symmetric converted phases from radial and tangential RFs vs. back-azimuth. These patterns can be explained by the presence of dipping interfaces and/or anisotropy within the crust. We then inverted RFs following the inversion scheme proposed by Sambridge <1999>. The results show the presence of S-velocity inversions in the lower crust beneath the Apennines, the upwelling of Moho in the Tyrrhenian area and its progressive deepening from the Tyrrhenian Sea toward the Adriatic coast.