Vehicular Ad Hoc Networks (VANETs) are considered as a special case of mobile Ad Hoc Networks (MANETs) and are recently gaining a great attention from the research community. The need for improved road safety, traffic efficiency and direct communication along with the great complexity in routing, makes VANETs a highly challenging field. Routing in VANETs has to adapt to special characteristics such as high speed and road pattern movement as well as high linkage break probability. In this paper, we propose an enhancement mechanism for the GPSR routing protocol and present its performance for urban and highway scenarios. Its performance is compared to the performance of the most common MANET routing protocols adopted in VANETs. The proposed enhancement is shown to be beneficial in most occasions as it outperforms the rest of the tested routing protocols.