First, some of the floor of a long wooden shed to the west of the Westbourne Park site, originally designed to hold trains in Brunel's broad gauge, later converted for standard gauge. One track was in front of the fence at the back (which separates the site from the working tracks), another was much closer to me but unfortunately doesn't show well in this photo. The central troughs under each track were for inspection and drainage, since trains were cleaned and washed there. This isn't as clear as I would like, I seem to have lost another that showed things much better better - or I didn't actually take it when I thought I did. The bit with jumbled bricks between the two tracks is apparently left from the demolition of the original shed some time in the early 20th century.
Next, the foundations of a railway turntable that served various engine sheds and sidings, which was in the middle of the site. They think that this was for standard gauge trains. Unfortunately there isn't much left apart from the foundations. It was probably turned by hand, using some sort of ratchet system. They think that at some point it was lengthened, which is why there are two circles of foundations for the outer ring of the turntable. The two square structures were added in when the turntable was enlarged; the archaeologist (the guy in the yellow jacket in the second picture) wasn't quite sure what they were for.
Finally, the remains of another engine shed at the west end of the site, this one designed for standard gauge. This was used for servicing and cleaning engines, and everything is blackened by endless showers of sooty water and waste. Any red brick you can see was exposed when this was dug up, because the original surface was completely covered. That also applies to most building in the area of that period, including the front of my house. The metal grid I've shown is a drain, one of the few metal items they've found at the site. The others were a few short bits of broad-gauge track, some broken tools, and a manhole cover, all of which will be going to a railway museum.
There should eventually be plans and models exhibited, and reconstructions of the buildings. It's a shame that more of the site can't be preserved, but I think even Brunel would prefer there to be a working railway there again.
While these photos may not look incredibly exciting, it was actually quite an interesting visit - there's apparently going to be another site opened to the public early next year at Liverpool Street, concentrating on Roman artifacts etc. they've found, and probably open for a week or two rather than a single day. I'm looking forward to it.
official photos etc. here