A trapdoor assembly for use on railcars is provided. The trapdoor assembly is pivotable between an up position and a down position. In the up position, the trapdoor assembly provides access to stairs on the railcar so that passengers can egress between the railcar and a ground level platform at a rail station. In the down position, the trapdoor assembly covers the stairs and provides a platform so that passengers can egress between the railcar and an elevated platform at a rail station. The trapdoor assembly also includes an extendible platform for bridging the gap between the railcar and the elevated station when the trapdoor is in the down position and the railcar is stopped at the elevated station.