Main street-level entrance to the Arsenal'na station for the "red" in Kyiv, Ukraine.
This station has possibly the deepest platform in any underground station in the world. It needs two sets of escalators, to get from the street and turnstiles to the actual train platform. The escalator sets themselves go about 50 metres up and down, making it about 100 metres underground. It takes just under ten minutes by escalator to get from the street to the platform.
Photo by Josh Hanz on 11 October 2009 (josh_hanz @ hotmail.com)