Equestrias mainline network as of 1006 CR (Branchlines and private lines not included)

Equestria didn't always have a unified railway network, but the Network as we think of it was first formed in 850 C.R. with the Canterlot, Ponyville & Dodge City Railroad (C. P. & D.C.), In 865 Hoofington became an interchange between C.P. & D.C. and the Hoofington, Los Pegasus & Tall Tail Railway (H.L.P. & T.T.R.).

Meanwhile in the east The Canterlot, Manehattan and Trottingham Railway (C.M.T.R.) was being built, being completed in the 880s, later a secondary main line to Hollow Shades was built. though a boat service still reaches trottingham, the Griffish Isles are still largely untouched by railways, with the exception of a few local 2 foot gauge lines serving the coal mines.

In 885 the Baltimore and Fillydelphia was completed, and in 890 it linked up with Canterlot.

Whilst these were being built a massive project was underway: The Great North Western Railroad, Stretching from Canterlot to Whinnyapolis and stretching up and around the crystal mountains to the Griffon lands, meanwhile in the south it would continue to stretch to Vanhoover, Which the H.L.P. & T.T.R. had since connected with.

In 950 The railway companies made a pact, to form one, enormous network, linking the the whole of equestria under one company: The Equestrian National Railway (E.N.R.)
The E.N.R. appointed a Mister Trotchard Gearvithic as the Chief Mechanical engineer, based at the former Canterlot, Ponyville & Dodge City Railroad works in Canterlot, and later that year he produced the "5-hoofer" 4-4-0, the "3-hoofer" 2-8-0, and the "4-hoofer" 2-6-0 as the "engines for the future" with the externally-contracted Trotnell "2-footer" 0-4-0ST joining as the main shunter in 960.

Whilst The rest of the network nationalised, the GNR remained a somewhat separate affair, becoming the Whinnyapolis, Yakyakistan, Crystal Empire and Griffinstone Joint Railway (WYCE & GJR) with the return of the Crystal empire.

The track is maintained by the ENR, but locomotives and rolling stock are unique to the route, noted for their highly inclined cylinders and "mechanically driven valves", whilst the locomotives on the rest of the ENR have arcane driven valves.

In 989, due to deteriorating health, Gearvithic stepped down as CME of the ENR, and was replaced by the young Emerald Night, she had moved from the regional control at the then GNR,

4794090 I think the line off the northeastern railroad should be a separate railroad

4794090 In 1006 Luke Washington Joined the ENR as a trainee driver AND assistant mechanical engineer, Pretty soon he began to notice a number of problems with the current system:

1. Most locomotives were ageing at best, with a number dating back to BEFORE the unification.

2. even the most up to date locomotives were struggling with the train loads, due to the ENR's policy of a small number of classes for a wide range of work, this coupled with a small engine policy meant the railway was on the way to bankruptcy.

3. The railway still retained many of the former rivalries between individual railway companies, with locomotives still retaining the liveries of old companies.

4. It also retained signalling systems and operational policies from the old companies.

Henceforth, he began to write out a plan of modernisation and standardisation to bring the railway into the new millennium, these included in no particular order:

. re-structured management system

. A network wide, standardised set of liveries.

. A network wide renumbering policy

. New, larger locomotives built using standardised components, designed with future traffic demands in mind.

. rebuilding or withdrawal of older classes, using standardised components for rebuilding.

. A new, simple yet eyecatching symbol with network wide rebranding to match:

. A fresh PR-department tasked with advertising and promoting rail travel.

. re-organised maintenance schedules to maximise the availability of locomotives and rolling stock.

. New fares system

. long-term aim of reducing carbon output via network-wide electrification and conversion of locomotives, powered through renewable sources such as solar panels, wind farms, and hydroelectric dams.

. Improved trackwork, signalling and infrastructure.

Charter and special trains to cater for special events

Upon formation the ENR numbering went like this, not far from BR's:
HLPTTR: unchanged (GWR)
CMTR: 30000 added to original number (SR)
CPDCR: 40000 added to original number (LMS)
BFCR: 60000 added to original number (LNER)
Numbers higher than 70000 were allocated to new locomotives of the following powers and arrangements, many built with Walschevaal or Cavalli valve gear and all with Belpaard fireboxes (orange indicates actual BR designs, turquoise my own, although I must cite that the 4P 4-4-0 and the 10F are not mine but were developed by me):

2G (2-6-0)
2G (2-6-2T)
3P2F (4-4-0)
3P (4-4-2)
3P2F (4-4-4T)
3G (2-6-0)
3G (2-6-2T)
3G (2-6-4T)
4P3F (4-4-0)
4P (4-4-2)
4P3F (4-4-4T)
4G (2-6-0)
4G (2-6-2T)
4G (2-6-4T)
4G (4-6-0)
5P4F (4-4-0)
5P (4-4-2)
5P4F (4-4-4T)
5G (2-6-4T)
5G (4-6-0)
6P5F (4-6-0)
6P5F (4-6-2)
7P6F (4-6-2)
7P6F (4-6-4)
7G (2-8-0)
7G (2-8-2)
8P (4-6-2)
8G (2-8-2)
8G (2-8-4T)
8G (4-8-0)
8F (2-10-0)
9P8F (4-8-2)
9F (2-10-0)
10F (2-10-0)

Diesels and electrics were built in similar classes and were kept in different numerations like the above but were respectively preceded by "D" or followed by "E."