I received a parcel in the post from Japan, containing an oval of Tomix "Mini Fine Rail", and, following some experiments, have discovered that it *should* be possible to build a roundy-roundy-style layout in N scale within a 1-foot width board. Experiments with a Farish 04 shunter and some Peco SWB wagon kits show that they will run around the 140mm radius curves (admittedly with some grinding noises from the wheels of the 04), although the Rapido couplers will not work reliably on the curves. However, I have an idea for a modification which may work, but more of that later. The other issue with such sharp curves should be obvious to anyone who's ever built a setrack layout: the number of wagons required to take up a given arc on a curve. Obviously, on your "average" prototype curve, you would need a great many vehicles to take up a few degrees. On these curves (which scale up to about 1 chain radius - half the official minimum operational radius of the class 04!) five 10' wheelbase wagons appear to take up 90 degrees... This leads to some wonderful views from above, such as:

This also leads to a slightly ridiculous appearance when running bogie coaches, as three mark ones take up an entire 180 degree curve by themselves. I think I might have to use four-wheelers.

However, in terms of appearance, the track isn't that bad, being pre-ballasted, but with a lower ballast shoulder than Kato Unitrack. Sleepers appear to be slightly under scale length for UK track, but this may be to do with the overscale rail clips:

There are two small gaps moulded into the ballast in each track section, for the neat power clip.

Also, Tomix produce their smaller-radius curves (at least, I am not aware if they do this for larger-radius ones like this) with infill between the rails and outside them, because the smaller curves (known as "Mini Fine Rail") were originally designed for modelling tram lines. Therefore, they may be of use to modellers looking to reproduce dockyard track on their layouts. However, Tomix's products are not widely known of outside of Japan, and are almost impossible to obtain outside the country.