At least part of the problem with Holborn is the station's horrific design. Each platform has only one entrance, and if you want to change from the Central to t

At least part of the problem with Holborn is the station's horrific design. Each platform has only one entrance, and if you want to change from the Central to the Picadilly line (which many do) you have to walk directly through a flow of people who queuing for the escalator to exit the station. This is compounded by the high number of tourists using the station (usually on their way to Covent Garden, or doing the aforementioned change.) For such an important station in London's infrastructure, the actual station design is terrible.