The presence of roads in any landscape is known to negatively influence terrestrial and aquatic ecosystems. Many tourist destinations and religious enclaves in developing countries are inside protected areas (PA). They are well connected by roads and attract thousands of visitors. The effect of such large human congregations inside PA on biodiversity is not well understood. Here, we address the impacts of increased vehicular traffic due to religious tourism on local fauna inside the Kalakad Mundanthurai Tiger Reserve in south India. We sampled sections of surfaced roads for mortalities before and during an annual festival across three habitats in 2008 and 2009. Millipedes, anurans, insects and reptiles dominated the mortalities and mammals avoided the roads. A total of 1413 individuals belonging to 56 species were killed on roads. Nocturnal species constituted 50% of these mortalities and 64% of the species composition. There was a 299% increase in road mortalities and 648% increase in nocturnal species mortality during the festival compared to those before the festival. Mean mortalities varied across habitats and were highest in moist deciduous forests. Mortalities were influenced significantly by vehicular traffic rather than rainfall. Indications of a temporary local extinction were evident beyond certain threshold of vehicular movement. The number of vehicles plying on the roads was three times higher than the threshold level as determined in this study. The festival also had a spillover effect by causing increased mortalities on roads not connected to the temple. We discuss several strategies to minimize impacts due to large scale vehicular movement inside protected areas.