Game design by Simon Cook. The road drawing technique and object manipulation were designed by Richard Underhill and Mark Haigh-Hutchinson. Darren Pegg (trading under the name of P.M.S. Systems) wrote the Amiga and Atari ST versions, but seemed to forget the concept of hills going down as well as up - so Richard was not particularly honoured with the credit! Richard wrote the C64 version and Mark wrote the Spectrum & Amstrad versions [Source: Richard Underhill].