Population per 2001 census:
Ashford 58,936
Gillingham 99,773
Chatham 70,540
Rochester 27,000
Strood 33,182
Total 230,000 (approx)
Hmm, obviously makes sense to start the train from Ashford rather than Gillingham (before proceeding to Maidstone, Tonbridge, etc. on either route)...