55020 (L120) arrives at Heyford station on 20 February 1982 with the 12:22 Oxford to Banbury local service. It is hauling one of the unpowered DTS vehicles that were built at the same time for use when a single unit was insufficient. Although 55020 is still in use (although not on this route), virtually everything else in this picture has changed. The substantial stone built station building was demolished a few years after this picture was taken and even the road bridge has now been completely rebuilt.

In 2003 Chiltern Railways refurbished 55020 (121020) and painted it into this smart blue livery with silver banding. The work also included the fitting of secondary door locking, which made it exempt from the mass withdrawal of Mk 1 stock at the end of 2005. This work was done to release a Class 165 for refurbishment. On 14 July 2003, it is pictured passing North Lee with the 18:55 Princes Risborough to Aylesbury service. The single car unit was ideally suited to this short distance shuttle service.

55020 (121020) passes milepost 45¾, as it heads through the trees near Little Kimble with the 09:17 Princes Risborough to Aylesbury Chiltern Railways service on 24 May 2010. Nearly fifty years old and still earning a living on the national network - not a bad record and something that a lot of modern units will probably never achieve. However, this vintage unit doesn't exactly have a demanding schedule, being confined to morning and evening peak trains on this quiet local line.

55020 (121020) approaches Little Kimble on 24 May 2010 with the 09:40 Aylesbury to Princes Risborough Chiltern Railways service. This picture was taken two days after the final slam door EMU trains ran on the national network, and proves there are still doors to be slammed! Just a couple of Pressed Steel 121s soldier on lightly loaded branch services. The unit is just crossing over a farm occupation underbridge, the wooden gateposts for which have provided a nest site for a pair of blue tits. Obviously the trains passing within a few feet of the nest did not worry them.

55021 (L121) heads past Hinksey Yard with the 13:40 Oxford to Didcot service on 22 October 1985. Surprisingly this short distance journey was a non-stop service, ignoring the intermediate stations of Radley, Culham & Appleford. The waste ground behind the corrugated iron fence is the site of Oxford gasworks, the lack of vegetation being the result of industrial contamination of the soil. The white lattice steel bridge visible directly above the DMU allowed the works railway lines to cross the River Thames. This view offers a panoramic view of Oxford, from the Ice Rink (the structure on the extreme left) to the Castle (centre) and the nearby spire of Nuffield College.

960014 (977873 or the former 55022) is pictured at Hatton North Junction with the 5T51 Bicester to Stourbridge Chiltern Railways route learner on 19 February 2008. The drivers under instruction can just be seen in the cab, highlighted by the low winter sun. In 2008 over half this class of 'bubble car' are in departmental service as route learners or sandite vehicles, albeit with a number of vehicle stored. They must therefore be considered as one of the most successful and useful of the first generation DMUs.

I don't normally take close up pictures of trains after taking the main picture, but this is such an interesting vehicle that I made an exception. Departmental 960014 (977873) passes Hatton North Junction with the 5T51 Bicester to Stourbridge Chiltern Railways route learner on 19 February 2008. The former 55022 is a real blast from the past with its faded blue and grey livery, even though in its later days in passenger service it was painted in Network SouthEast colours. The discrete Chiltern Railways logo and the radio pods on the cab roofs are the only give away that this is not a 1980s picture, and of course the two different departmental numbers carried on the front and the bodyside!

I had been meaning to photograph the 3S74 08:46 Aylesbury to Marylebone Rail Head Treatment Train for some weeks, so when a sunny day was forecast for Saturday 6 December 2008, an early morning trip was made to the Aylesbury area. As the sun would have only just risen when the train was due, it was a good job that I knew a spot that would be ideal, with nothing in the way to shade the train and the sun at the perfect angle. Of course this carefully laid plan was thwarted by a band of cloud that formed just where the sun was! 960014 (55022) & 960010 (55024) are pictured passing North Lee on time and in no light whatsoever! Much careful work in Photoshop has brought out the underframe detail and also retained the subtle tones in the sky. Without the use of layers this picture would either be excessively dark or have the all too common fault of railway pictures on websites - that of a completely blank sky.

55023 (L123) heads away from the camera at Aristotle Lane, Oxford with the 10:07 Didcot to Banbury local service on 11 February 1985. This unit can still be seen today, not too far from this location, as it preserved at the Chinnor & Princes Risborough Railway. Directly behind the unit are the Trap Grounds allotments, which have been threatened with housing development for many years, the fact that they are on the wrong side of the railway with only a footbridge crossing has always being a stumbling block, along with the allotment holder's fierce resistance. In the distance is the snow covered expanse of Port Meadow.

55024 (L124) approaches Wolvercote Junction on 20 August 1987 with the 2M60 17:50 Oxford to Banbury service. In the mid 1980s a single car unit was quite sufficient for the local traffic on this route, but would certainly struggle today. 55024 has obviously not long returned to service after a repaint, with the exhaust stacks in particular being particularly pristine.

55024 (124) traverses the single track line from Bicester and approaches Oxford North Junction with the 07:59 Bicester Town to Oxford service on 25 June 1988. This was the first up train of the day on the line and at the time was a non-stop service as the intermediate station at Islip was still a year away from re-opening. The curve that 55024 has just traversed is product of the 1970s track rationalisation of the area. Originally this former LMS line carried straight on parallel with the former GWR lines towards Oxford.

The highlight of the Chinnor & Princes Risborough Railway's Diesel Gala on Sunday 17 October 1999 was the use of Railtrack Sandite unit 55024 (977858). It is seen here just having arrived on the line at Thame Junction, and accelerating away towards Chinnor. I chose a side view from the nearby field to show off the unique livery. Plenty of detail for modelers in this picture. Note that the condition of the roof hardly matches the immaculate condition of the rest of the vehicle!

55025 (L125) heads south from Shiplake, on the Henley-on-Thames branch with the 13:44 Henley to Twyford service on 5 March 1988. This is branch line operation in a barely updated form from GWR days, as the Class 121 'bubble cars' are a direct replacement for the Great Western's pioneering 1930s railcars. Unfortunately I took very few pictures of the branch before the arrival of the Turbo units in the early 1990s, but there was obviously so much happening on the railways in the 1980s that it had a low priority!

Hallen Marsh Junction, near Avonmouth is a location that has changed dramatically in the last few years. In 1987 the signal box controlled a forest of semaphore signals around the junction area, with well over a dozen signals in view here. Unfortunately all this steam age equipment has now been swept away. On 15 August 1987, 55026 (B126) passes the junction with the 17:36 Severn Beach to Bristol Temple Meads service. The lines leading off to the right went to Commonwealth Smelting and ISC Chemicals, while the lines branching off right in the background head towards Filton, and still see freight traffic today. Between the Filton line and the line to Severn Beach can be seen the rail served Chittening Estate.

In 1994 the Network SouthEast liveried 55029 was smartened up with the addition of a white cab roof (which the class originally carried when they were in green livery), red buffer beams, and silver buffers and exhaust stacks. It is seen here leaving Ridgmont on 16 July 1994 with the 11:40 Bedford to Bletchley service. At the time the Bedford to Bletchley line was something of a time warp, not only with classic traction, but semaphore signalling and hand operated level crossing gates.

55029 (L129) & 55027 (L127) pass Kempston in glorious evening light on 11 July 1996 with the 18:40 Bedford to Bletchley service. Although both units carry the later version of Network SouthEast livery, 55029 has been spruced up with a white roof, black window surrounds and a red buffer beam. Although an ideal photographic vantage point, this is not a very pleasant spot to wait for any length of time, as it is on the Bedford bypass, and the traffic is both heavy and constant.

An odd combination at West Drayton on 22 June 1991 that proves the usefulness of the first generation DMUs. 55031 (L131) has been made into a three car set with the addition of a Class 101 DTCL and a Class 117 DMBS. It is pictured on the up fast line with the 12:10 Reading to Paddington Network SouthEast service. This train is an all stations service as far as Slough, from where it becomes non-stop to Paddington. Due to the closure of the relief lines just east of this point for engineering works, this Class 121/101/117 DMU lash up has been let out onto the main line to rattle its way to the capital at 70 mph in a gap between the HSTs!

55033 emerges from the fog at Blackwell on 25 May 1992 after having just climbed the Lickey Incline whilst working the 07:26 Bromsgrove to Barnt Green service. This is the only photo I have of this unit in its Midline livery, but note that it has had a door replaced with one from a standard blue and grey unit! Also the Tyseley set number (TS013) seems to have been hastily applied on top of its former designation (T133). I presume it is supposed to read TO13 but it actually shows TO133!

Although I managed to photograph all the Class 121 DMBS 'bubble cars', I only ever saw 55035 twice. Withdrawn from revenue earning stock in 1978, it survived in departmental use as route learner ADB975659 until 1992. Initially it carried the set number L103, but by 1988 this had changed to L135. On 20 April 1988 it is pictured approaching Bathampton, between the River Avon and the Kennet & Avon Canal with a Southampton to Bristol route learning trip. Luckily it just managed to beat the approaching clouds!

54283 (283) is propelled by 55031 (131) towards Oxford on 25 June 1988 whilst working the 07:58 Banbury to Oxford service. They are pictured approaching Oxford North Junction with the up relief line (which runs from Wolvercote to Oxford) prominent in the foreground. Although both vehicles carry Network SouthEast livery, note the slight differences in livery between them, with slightly different widths to the grey bands and what appears to be a red rather than orange cantrail stripe on 54283. While in common with most Class 121 DMBS vehicles 55031 survives in departmental use, unfortunately the same cannot be said of 54283, which like most of the DTS vehicles has since been cut up, in this case at Gwent Demolition at Margam in 1992.

In addition to the 15 single car Class 121 DMBS vehicles, 10 additional unpowered DTS vehicles were also built. These were normally used with a Class 121 to form a two car unit, or as a spare vehicle for a Class 117 three car set. 54286 (L286) is seen here approaching Combe station on the Cotswold Line, being pushed by 55027 (L127) on 21 August 1982 whilst working the 06:10 Moreton-in-Marsh to Oxford local service. The very high occupation bridge in the background is Grintleyhill Bridge, while on the left the piles of timber are on the premises of the Blenheim Palace Estate timber mill and workshops.