Mansion House - Member Layout

by Stephen Grant

The legend

The London and South Western Railway had a problem. In 1848 it had moved its London terminus from Nine Elms to Waterloo but this was still some distance from the City, the ultimate destination for many of its passengers. The South Eastern had Cannon Street, the LCDR had Holborn Viaduct, the LBSCR had London Bridge and railways north of the Thames had access to the City at Liverpool Street, Fenchurch Street and via the Metropolitan Widened Lines to Moorgate but businessmen arriving at Waterloo were faced with a horse-drawn cab or bus ride, a wait for a ferry or a long walk to their City offices. The LSWR had tried exercising running powers over the LCDR to Ludgate Hill but there was simply not enough capacity on this rather tortuous route to accommodate an adequate service.

In 1891 a separate company sought the LSWR’s backing for an electric tube railway from Waterloo to Bank but, as one of the LSWR’s directors put it; “Gentlemen with business in the City will not expect to descend into the Drain to reach their destination”. He won the argument and the Company decided to build its own City extension as a ‘proper’ railway for its most well-heeled and influential customers.

The new line, which opened in 1895, consisted of twin tracks from a junction north of Vauxhall to a pair of low-level platforms on the south-eastern side of Waterloo. It then dived under the South Eastern Railway’s Charing Cross and Blackfriars lines before climbing on arches to cross the Thames on a steel plate-girder bridge at Queenhithe, a short distance upstream from Southwark road bridge. The new City terminus on the north bank of the Thames took the name Mansion House from the adjacent Metropolitan District Railway station.

There was only room (and funds) for a five-platform station and the cramped site limited train lengths so the new City terminus never rivalled Waterloo itself - its principal purpose was to serve the stockbroker belt of Surrey and northern Hampshire and to convey more junior workers into the City from the rapidly developing south-west suburbs of London.

The LSWR and the London Tilbury and Southend Railway jointly built a further extension from Mansion House via a tunnel beneath Aldgate to a connection with the LTS at Leman Street. The intention was to operate through suburban passenger services but these never prospered and, within a few years, the Aldgate line was relegated to a cross-London transfer freight route and the low level platforms at Mansion House fell into disuse.

The LSWR incorporated its City extension into its suburban electrification plans from the outset and the line was later resignalled with colour lights as part of the Southern’s 1936 Waterloo scheme, its signal box on girders high above the murky Thames being re-equipped with a Westinghouse power frame.

Today, following a glass-and-steel redevelopment of the site, no trace can be seen of the 1895 station which has now, of course, been replaced by new sub-surface platforms on the Thameslink Two route, but an hour spent at the end of Platform 1 at Mansion House sixty years ago would have yielded a rewarding range of trains. The most frequent were the humble suburban electrics to Hampton Court. ‘4-Cor’ and ‘2-Bil’ electric multiple units operated services to Portsmouth Harbour and Alton/Guildford respectively, alternating with services from Waterloo to give half-hourly frequencies on both routes. Hourly semi-fasts to Basingstoke and Salisbury were steam-hauled, usually in the hands of a Bulleid Light Pacific or a Standard Class 5 but occasionally one of the remaining ‘King Arthur’ 4-6-0s might turn up. These services generated light engine movements to and from the Southwark servicing point where the locomotives would be turned and watered in readiness for their return trip. To add further variety, a freight from the East London docks might emerge from the sulphurous depths of Aldgate Tunnel and slowly plod across the Queenhithe river bridge or a parcels train to Tilbury might clatter across the junction and descend the incline.

The model

Back in the 1960s I was inspired by CJ Freezer's classic layout plans 'Minories' and 'A Thoroughgoing Terminus' As he pointed out, it is easier to justify a cramped layout in a city environment where space is at a premium; furthermore I find it easier to model brick and concrete than to create a convincing rural scene of fields, trees and hedges.

I have always been fascinated by railways in a city landscape, by glimpses of London's railways emerging in canyons between tall buildings or diving under other lines to lead...who knows where? With his particular fondness for the smaller, less well known corners of the capital's rail network John Betjeman evoked these atmospheres better than anybody; the old Liverpool Street station on a foggy evening, snow falling on the abandoned Aldersgate station, Cannon Street (before its ghastly 1960s rebuilding) "so echoing, so lofty and so sad".

With these influences in mind, the model represents Mansion House station as imagined about 1959. The era is rather loosely defined as I believe that if one can invent an entirely fictitious railway one can manipulate prototype building and scrapping dates by few years in order to run the trains one wants. Thus a suburban unit with ex-LSWR bodywork (rebuilt as an all-steel EPB unit in 1956) run alongside rebuilt Bulleid Pacifics and Standard Class 5s bearing evocative names from Arthurian legend (inherited from scrapped Urie N15s in the early 1960s). Similarly, the individual locomotives that work in and out of Mansion House were in reality based anywhere from Ramsgate to Exmouth Junction at the time.

Rolling stock

A London townhouse, a young family and a career left me with little time, money or space to indulge my model railway plans but I slowly built up a collection of the rolling stock I wanted.

In the 1970s and 1980s, with Wrenn gradually fading from the scene, I hastily bought some rebuilt Bulleid Pacifics - after all, nobody was likely to bring out new models of such obsolete prototypes, were they? Likewise I painstakingly and inexpertly assembled two DJH Standard Class 5s, another 'must have' type that the declining model railway industry seemed unlikely to replicate in future. Today, of course, these types are readily available as superb RTR models but my much-adapted Wrenn Bulleids still have a certain presence, despite a cab full of Ring-field motor and, despite my worst efforts as a model-maker, the DJH Standards run fairly well.

Wills whitemetal King Arthur and T9 locomotives, an early Bachmann Standard Class 4 and some more modern locomotives; a Bachmann 'N' class, a Hornby M7 and a Hornby streamlined Bulleid Pacific complete the steam roster.

The Southern Electric fleet is equally eclectic. A pair of Marc Models kit-built 4-Cor units handle the Portsmouth Harbour semi-fast and Hornby Bil/Hal units cover the Alton/Guildford service. Suburban units include a kit-built Roxey LSWR-bodied Sub with a No Nonsense Kits all-steel augmentation trailer, an all-steel 4 Sub professionally built by Marc Models and another unprofessionally assembled by me.

Originally, most of the kit-built electric multiple units used Tenshodo 'Spud' motor bogies but all too often these simply do not run smoothly and reliably enough so I have since replaced the worst of them with either Hornby or Black Beetle motor bogies.  A few of the better-running Spuds survive.


Retirement and a move to Cornwall yielded, among other things, a block-built shed that had previously housed a goat. Eviction of the goat, a new roof, internal dry-lining and installation of a power supply has given me a 9.6m x 2.4m internal space in which to realise my long term vision. As I do not intend to exhibit the layout I have been able to plan it as a fixed installation without the constraints of portability.

A twin track route links the five-platform terminus to a return loop and a set of storage sidings, with the 'Aldgate Lines' bypassing the terminus to complete a circular route as an alternative to 'out and back' operation. Steam locomotives are turned and watered at a servicing point on the Southwark side of the river, based on the GWR's Ranelagh Bridge and the LNER's Kings Cross Yard, so as to minimise light engine movements to Nine Elms shed.


The scenic side of the layout takes up one wall. The five terminal platforms and the Aldgate Lines rise from a cut and cover tunnel beneath the station buildings, all funnelling on to the scale-length, twin track Queenhithe Bridge, spanning the Thames.

In the late 1950s the river was still lined with warehouses served by barges and lighters towed from London Docks and these will be reflected in the modelled buildings; a mix of Scalescenes, Metcalfe, Kingsway and scratch-built structures, together with an occasional, much-modified Bilteezi veteran.

The riverbanks are Polyfilla powder mixed with emulsion paint and built up in layers, with a dilute version of the mix painted on by brush to fill up cracks as the plaster dries and shrinks. The colour was finally adjusted using acrylics and coarse ballast scattered to simulate the mud and pebbles of the real riverbank at low tide. The river itself is graduated shades of emulsion and acrylic paint, overlaid with several layers of clear gloss varnish.

The south bank was more industrial than the City and had at the time a distinctly low-rent atmosphere. The layout here is dominated by the Southwark locomotive servicing point which stands squarely on the actual site of Shakespeare's Globe theatre. The main line descends from the river bridge to disappear from sight beneath the Metropolitan Junction-Blackfriars spur of the Southern's Eastern Section and, supposedly, onwards to Waterloo Low Level and a grade-separated junction with the South Western main line.

Storage sidings

The other side of the shed consists of a return loop that feeds seven storage sidings, enabling trains to be made ready to return to Mansion House without physical handling. A further advantage is that the turned train shows its other side to the observer, reducing the sense that the train that only just left is back again. However I could not bring myself to give each locomotive two different cab-side numbers!

In addition to the return loop, a pair of tracks (the "Aldgate Lines") makes a complete circuit of the shed. During timetabled operations these tracks can be used to run and store cross-London freight and parcels trains; they are also very handy for those occasions when one just wants to run a train round and round.


PanelThe Up and Down lines each have a Gaugemaster controller feeding current to the tracks through a Gaugemaster track cleaning unit.  Nothing fancy, but the result is very satisfactory slow running; important for a terminus layout.

As the layout is fairly complex and something of a challenge for a single operator, I have constructed a control panel with route-setting switches, each of which operates the appropriate relays for point motors, supplies traction current to the relevant lines and switches signal aspects for the non-automatic signals. A subsidiary panel operates the Southwark loco yard.

Many of the points are on the Queenhithe Bridge and here I have used Fulgurex slow-action point motors as their shallow profile hides them between the bridge girders. However I have had some problems with reliable operation of relays on these points so elsewhere I am using the robust Cobalt slow-acting motor.


The platform starting signals use Eckon colour-light signal heads which, with their rounded backplates, convincingly resemble the Southern Railway's prototypes, mounted on my own design of etched brass brackets which are based on the structures installed by the Southern at Waterloo in the 1930s.  As well as three-aspect signals for Down departures, each platform has a single-aspect 'auxiliary running signal' for light engine movements over the reversible Up line from the station to the locomotive servicig point.  These signal aspects are set according to the route set on the contol panel.

Two of the other signals on the layout are automatic, paired with Heathcote Electronics MAS sequencers that detect a passing train and sets the signal to red and then on a timed sequence clears to yellow and green.


Membership of a model railway club has all sorts of benefits for an inexperienced modeller like me.

As well as the companionship of a group of individuals working towards a common goal such as preparing a club layout for exhibition, individual members have particular skills; in solving electrical and mechanical problems, in constructing realistic scenery, in laying and ballasting track, in prototype practice and so on.

There is no doubt in my mind that the layout as built so far looks and runs better than it ever would have done if I had relied only on my own skills and knowledge.

Stephen Grant

April 2017

Gallery - click to enlarge