After doing a circuit of Didcot Power Station, 56034 Castell Ogwr / Ogmore Castle emerges from the flyash loop with the imaginatively titled 'Didcot Lupin' railtour on 18 August 1991. This tour was organised by Hertfordshire Railtours, and originated at Paddington. This was the second tour of the day to do a circuit of the power station, as 56022 & 56025 had visited earlier in the day.