[Talk-GB] Miniature railway or minimum gauge?

[Mark Goodge]

On 20/05/2019 22:13, jc129 at mail.com wrote:
> On 18/05/2019 18:03, Mark Goodge wrote:
> 
>> The OSM wiki is correct to distinguish between miniature railways (ie,
>> ridable models) and small gauge "real" railways, as this reflects usage
>> among railway engineers and enthusiasts in the non-mapping community.
> 
> As I'm not a railway engineer or enthusiast I'm not sure what you mean,
> so please can you give specific examples?

The most important difference, from an engineering/enthusiast 
perspective, is whether the line was originally built for a functional 
purpose (passenger/freight transport) rather than being just for the fun 
of the ride. Obviously, most narrow gauge railways these days exist 
solely for leisure purposes, but many of them were formerly functional 
railways. If it was built as a functional railway, then - even if it has 
been significantly rebuilt in order to cater for the leisure market and 
no longer has any functional aspect in current usage - it's a narrow 
gauge railway, not a miniature railway.

If it was built purely for leisure purposes, then what makes the 
difference is, generally, the appearance.

A miniature railway is, essentially, a large outdoor model railway 
that's big enough for people to ride on. A distinguishing feature is 
that it makes at least some attempt to be a visual replica of a 
full-size train, or, at least, a full size loco. These are a few good 
examples:

https://www.railadvent.co.uk/wp-content/uploads/2016/05/NRM-Miniature-Railway.jpg

https://media.dayoutwiththekids.co.uk/media/15309/33373-kerrs-miniature-railway-arbroath-04.jpg?mode=crop&width=1680&height=940

https://i.ytimg.com/vi/UWgUbSkmGJA/maxresdefault.jpg

https://www.railadvent.co.uk/wp-content/uploads/2016/11/FR-Miniature-Railway-at-Tanybwlch.jpg

http://miniaturerailwayworld.co.uk/images/WeymouthBayMiniatureRailway.jpg

A narrow gauge railway, on the other hand, doesn't attempt to mimic 
anything bigger than itself - it's just a small (sometimes, very small) 
railway. Here are a few examples:

http://www.cheshirenow.co.uk/images_9/rdyd3.jpg

http://3.bp.blogspot.com/-_OKbvaNYSms/UFd4PYxK5QI/AAAAAAAAEkI/xSESbCLTM-Q/s1600/IMG_3625.JPG

https://c8.alamy.com/comp/ECFA5D/the-kirklees-light-railway-15-inch-gauge-railway-in-kirklees-west-ECFA5D.jpg

https://i.ytimg.com/vi/vf0lBvPbyy8/maxresdefault.jpg

It's important to note here that track gauge alone is not the 
distinguishing factor. Although miniature railways are, typically, 
smaller than the smallest narrow gauge railways (you can get a ridable 
model on as little as 5" gauge, which otherwise really is into model 
railway territory), there is a lot of overlap. Although 15" gauge 
(otherwise known as "minimum gauge") is generally considered the lower 
limit of true railways (as opposed to models), there are a few examples 
with track gauges smaller than that. The Wells and Walsingham Light 
Railway, for example, has a track gauge of only 10.25", but is not in 
any sense a model railway and hence not normally considered a miniature 
railway:

https://en.wikipedia.org/wiki/Wells_and_Walsingham_Light_Railway

Meanwhile, there are also plenty of miniature railways that use 15" (or 
even larger) gauge, simply because there are lots of commercially 
available products in that gauge. So gauge alone is not the deciding 
feature, even though it is an indicative one.

 From a mapping perspective, therefore, there are two questions which 
need to be asked:

1. Was the railway originally constructed purely for leisure purposes?

2. Are the locomotives intended to be models or replicas of full-size 
locomotives (or are otherwise "faked", such as petrol-engined locos 
designed to look like steam locos)?

If the answer to both questions is "yes", it's definitely a miniature 
railway. If the answer to both are "no", then it definitely isn't.

Where it gets fuzzy is where the answers differ. The Romney, Hythe and 
Dymchurch Railway, for example, has locomotives that are models (or, at 
least, modelled on) full size steam locomotives. But it's considered a 
narrow gauge railway, not a miniature railway, because, despite the 
eccentricities of its creators, it was intended as a public service with 
paying passengers and freight transport rather than merely as a leisure 
operation.

 From a mapping perspective, you can't always answer the first question 
from observation (although it can sometimes be inferred from the 
topography - "fun" lines are usually continuous loops or out-and-back 
layouts, while a point-to-point design - particularly a long one - 
often indicates a formerly functional railway). The second is amenable 
to observation, although you do need to know what you are looking for. 
But unless it is obvious either way from observation, then the best 
classification is whatever the operator calls it.

Mark