It's a tour bus which visits ghostly places (or something like that).
And I got a mail from Linda, who has informed me that this is the it is the last remaining Standard D Bus, known technically as a CIE Bodied Leyland Atlantean PDR 3A. Some of you reading this would have got these busses to school. The thing to recall is that they didn't have tinted windows, so on summer days there was a fiery brand of upper-deck sunlight which modern busses have since done away with. (more of these busses - 1 2 )
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