The very first connection with the TPO service is a little hazy. There is strong reason to believe that from the outset the line from Blisworth to Peterborough conveyed mails prepared on TPO's using the London & Birmingham railway. The "Rutland & Stamford Mercury" reported in December 1845 that the Post Office had signed a contract with London & Birmingham Railway to convey mails over the line from Blisworth to Peterborough including mails from the moving railway post office, undoubtedly a TPO, almost certainly Peterborough's first ever association with the service.
Whether a TPO, Sorting Carriage or Bag Tender ever traversed the line in the very early years is open to conjecture. It is known that in 1892 Bletchley to Peterborough and Blisworth to Peterborough Bag Tenders, and Peterborough to Bletchley and Peterborough to Northampton Bag Tenders existed. It is also a matter fact that in 1889 a working timetable produced for the southern area of the London & North Western Railway, designated the 8pm ex Peterborough for Rugby and the 2.10am ex Rugby for Peterborough as "Mail." It is curious that of all the great many trains listed in this working timetable, only this service was headed mail. Further to this, a Post Office Inspector known to the compiler of this history, and who worked in the Victorian era recalls a TPO service over this line. Add to this the fact that Wansford was known to be a Railway Sub Office, which, to obtain that status, received all or part its mail from a TPO, begs further questions. Finally, and which is referred to later, in 1966 the vital Peterborough to Rugby mail train ceased and a TPO was created as a result, not to mention the Nene Valley Railway.
Despite the best efforts of postal historians little is known of early TPO business. There is reason to believe that services of a short-lived nature proliferated in the early days driven by perceived needs that did not manifest themselves in practice. The sheer weight of traffic, increasing almost weekly, found the Post Office management struggling with a logistical nightmare, the like of which it had never encountered previously. Not unnaturally, desperate measures were called for and a classic example of this took place at Peterborough in 1856 when day mails between London and March, Wisbech and Kings Lynn were being seriously delayed.
It would seem logical to have mails for Norfolk and Cambridgeshire conveyed by the Eastern Counties Railway (ECR) but for these more northerly parts of East Anglia it was more expedient to bring them up to Peterborough. Once at Peterborough, it was a simple matter to transfer them to an ECR train, where in a very short time they would have arrived at their destination. At least that was the theory. There were however, problems that had to be overcome and that were peculiar to Peterborough.
Peterborough had two stations, the Great Northern Railway (GNR) station (to become known as Peterborough North) and the ECR station (to become known as Peterborough East). The London day mails arrived at the North station at which place they had to be off-loaded at the down side platform, put onto barrows and taken to a foot crossing where they were taken off the barrow and carried across the rails to the up side platform. This process would have taken 10 minutes at best to achieve. Then, once on the up side platform mails for the east would have been loaded onto a horse drawn cart or more probably a handcart. A 15-minute transfer between North and East stations would have ensued, and this would have been a best time. Once at the East station a further 5 minutes would have been required to off-load from the hand-cart and then onto the waiting train.
So, we have a situation where simply transferring bags from one train to another would have taken at least half an hour and any slight hiccup could have extended this time considerably. The Postmaster General had his surveyors investigate the matter and the ECR Company agreed to delay the departure of their train by ten minutes. This was to be of no avail and the situation required an urgent solution. As the London down mail arrived at Peterborough it passed within 400 yards of the ECR station when it passed over the London North Western (LNWR) and Midland Counties (MCR) lines, both of which had an end on connection with the ECR.
The Post Office, who had very considerable influence over the railway companies, were quick to realise that here was an instance where the TPO system could be used to good effect. They recommended the establishment of mailbag exchange equipment on the approach to Peterborough, on the GNR line, enabling the mails to be conveyed to the ECR station much more speedily - probably within 10 minutes. Sadly, despite rigorous investigation it has proven to be impossible to discover where precisely this exchange took place. As it was simply a train to lineside drop, it could have taken place on the embankment close to the bridge over the LNWR and MCR lines. Only a pick up from the lineside, requiring the use of the carriage net, would have imposed clearance restrictions.
All the major companies running into Peterborough had TPO's working over their metals with first coming into the city via the ECR route. The Cambridge District Sorting Carriage, according to J. G. Hendy  "...was extended to London & Peterborough (via Ely) on 15 September 1858...." H. S. Wilson suggests that this might be erroneous saying that the duty was expanded in 1867.
There is some evidence to suggest that in fact Hendy knew of an arrangement that provided for the sorting of mail between Peterborough and Ely in 1858 and if it was not the Cambridge District Sorting Carriage then it was another, as yet undiscovered mail sorting vehicle that was involved. A minute of the ECR dated 1858 stated that their Carriage Superintendent was required to raise the roof of a second class carriage, "....to allow the mail guard to deal with his letters between Peterborough and Ely..."
In those early days the need for vehicles in which to sort mail must have been a high priority for the Post Office, and the situation would have been fluid with the burgeoning railway system and the ever-increasing volume of letter mail. As with the lineside apparatus at Peterborough, urgent needs demanded immediate responses. The heightening of carriage roofs would have been a simple solution to a pressing difficulty. A mail guard was a title carried forward from the days of the horse drawn coach but had a different meaning in 1858 - it meant a grade similar to a postman/sorter. It is well known that very early carriages were not designed to accommodate standing passengers, hence the need to raise the roof. It is essential to understand that in those far off days 'necessity was the mother of invention' in every sense of the word.
Eventually an established service between Peterborough and Ely came into being in the form of the Peterborough & Ely Sorting Carriage that was established on 2 August 1869, replacing the Peterborough to London Railway Post Office of which little is know but may well have been the service referred to above. The Peterborough & Ely S. C. ceased on the night of 3/4 June 1916.
The Grimsby & Peterborough Sorting Carriage was a latecomer into the lists commencing on 1 April 1900 and ceasing on the 30/31 March 1917. This service ran over a well-established route, which opened in 1850 throughout and was always known by Peterborough railway and postal staff as "The Loop". Right from day one the Post Office had an interest in the line and a mail service was established under contract, the times of which the Post Office dictated. In 1850 the train for Grimsby left Peterborough a 2.00am - in 1960 the train carrying mails and traversing the same route departed Peterborough at 2.40am. It was still referred to as "The Loop" and was still a highly significant mail service.
The Great Northern Bag Tender was another service that ran through and transacted postal business with Peterborough. The GNR route is something of an enigma. It was a fast and efficient route between London and the North East, and onto Edinburgh. Strangely it was one of the last routes to have any kind of TPO service running over it and this is all the more curious when one understands that this line of railway ran along virtually the same route as the premier road of coaching days, the Great North Road.
According to Wilson in "The Traveling Post Offices of Great Britain & Ireland - Their History and Postmarks", Rowland Hill saw the establishment of the GNR as an attempt by a railway company to force the Post Office to use yet another service and was not at all enamoured of the idea. It would appear that a Bag Tender service was not established until 1871 and this was the first Post Office staffed mail service over GNR lines ! This is directly at odds with the information referred to above, where, in 1856, the Postmaster General requested and approved a facility for mailbag exchange equipment to be installed to ensure that the London Day Mails connected with Eastern Counties service.
It is very likely that the Post Office in the early days of railway operation set up ad hoc arrangements for sorting carriage and bag tender workings as and when they were required. The 1856 arrangement for mailbag exchanged on the Great Northern Railway and the raising of carriage roofs on the Eastern Counties Railway are typical examples. I strongly believe that many such services were tried and a great number were withdrawn with only the ones that became established being recognised and named as TPO services.
In 1910 a sorting duty was established (Great Northern TPO) followed by the creation of the London-York-Edinburgh and North Eastern TPO's. The LYE TPO has now finished and for a short period the NETPO did not run through Peterborough. At the time of writing, the NETPO continues to work through Peterborough but only runs between Willesden and Newcastle and is the last remaining TPO service to use Peterborough.
The East Anglian TPO began in 1929 and was the result of a major reorganisation following a period when numerous TPO's. District Sorting Carriages, Railway Post Offices and Bag Tenders proliferated throughout the eastern region. Connected closely with this service and also established as a result of the 1929 scheme was the Norwich - London TPO.
The last Peterborough staffed service was the Peterborough - Ely S. C. but there was always a heavy use of inter-connecting rail services from the busy railway junction city. When the EATPO commenced it had a section working from Kings Lynn via March and Ely and joining the main section at Haughley. This section was never really very efficient as it failed to deal with the increasing volume of distribution traffic. During the Second World War these services ceased and did not resume until 1946. Eventually, in October 1949 the Kings Lynn service was withdrawn and the service was extended to Peterborough.
At this time Peterborough was a significant General Forwarding Office and the influx of Eastern and Essex mails from Lincolnshire, the Midlands and Northwest were proving too much to handle. The establishment of the EATPO (Peterborough Section) was an inspired move and this became one of the hardest worked sections in the TPO network. For over forty years the Peterborough staff worked 'cheek by jowl' with their Norwich colleagues between their respective home stations and London Liverpool Street.
Although the Peterborough Section finished in 1990, as did the Norwich - London TPO, the East Anglian continues working between Norwich, Willesden and Dover.
In 1966 on 6th June the Peterborough - Crewe - Peterborough TPO came into being. This TPO has a direct link with the present Nene Valley Railway, for not only was it the cessation of rail services that ran over the metals between Peterborough and Rugby, and the subsequent loss of mail services, that inspired the creation of the TPO but also provided the trackbed for the NVR.
The Peterborough - Crewe services ran via Stamford, Leicester, Derby, Stoke on Trent to Crewe and return. At Derby the Lincoln Section, that had replaced the Lincoln - Tamworth Bag Tender, joined the main TPO. Over the years the route varied from time to time but basically remained as it commenced until its cessation in 1991. Peterborough and Lincoln crews throughout its existence staffed this TPO.
At the cessation of the Peterborough - Crewe TPO service, the Lincoln staff lost their TPO connection while the Peterborough staff crewed the Peterborough - Carlisle TPO that replaced it in 1991. This was not a return or 'out and back' service and Carlisle staff were required to work this mail on one side while Peterborough staff worked the other. This TPO went out from Peterborough following the route of the service it had replaced. Once at Crewe it proceeded northwards on the West Coast Main Line to Carlisle. On its return journey from Carlisle the TPO went across country to Newcastle and then southwards along the East Coast Main Line to Peterborough. In 1996 this service ceased and meant that after many years Peterborough no longer had TPO staff on its strength.
The TPO service has a long and proud tradition, which, over recent years, has become a very small part of the modern postal system. Many of its practices and internal systems of working have become diluted through modern management systems. It would appear that the Post Office or Consignia has come full circle and if recent staff/management enquiries are to be believed, the great period of Victorian postal agitation is with us again. Who knows but one day, Consignia may rediscover railways as a more efficient and environmentally friendly way of moving mail.