The last time I ran at Dorney Lake was in 2012 where it gave me my half marathon PB. Here I am going back again six years later to see what I can do and give me an indication of how my marathon training is progressing.
It has a slightly different name but it is the same organisers, F3 Events, and the same course, four unrelenting laps of the rowing lake going down one side and back up the central causeway where the rowing coaches ride up and down on their bicycles.
The start time us 12.30 so I don't have to get the first early morning train I remember from last time. I arrive at Windsor Riverside station alongside Windsor Castle and decide to walk the three miles to the lake. It's a beautiful day along the river path with swans out on the Thames, perfect for walking or picnicking but maybe a bit hot for running.

I get to the lake and head to registration, I get a real sense of deja vu as everything seems to be laid out the same as last time with the finish just around the curve at the end of the causeway.
There's a bit of a queue for number collection but soon enough I'm in the throng at the starting line. There's about 400 in the half marathon, there are also shorter races with slightly different starting points but because we are running laps we are all eventually going to be intermingled.

I'm nicely fed and watered well in advance, I've been to the loo and done my usual pre race exercise routine. It's my second race of the week but I'm feeling pretty good. A few wheelchairs are at the front and we take off twenty seconds after them. There's an out and back section of just over a mile on the far side of the lake before the laps start so that's far enough to get a feel of how the legs are and find my place in the stream of runners. I've started just about in the front half of the group but I find I'm overtaking a lot of people in this section with just a few coming past me. Soon enough we are into the laps. On a multi lap race it's always nice to get the first one out of the way.
And then, in dramatic fashion, a fly zooms into my mouth. It goes straight to the back and I can feel it right on my throat. I do the instant involuntary cough but there is no sign of it reappearing in my mouth. I've no idea if I've spat it straight out, swallowed it or it it still stuck at the back of my throat. It feels like the latter and it is restricting my breathing a bit but I try to relax and let things sort themselves out. After another half a mile or so it seems to be getting there. One of the wheelchairs goes by, he has lapped me, followed shortly after by the next. They are shifting.

After all this excitement a couple of laps have gone by. I'm lapping people myself, mostly walkers who are presumably in the 5K or 10K. It's hot and at the drinks stations - there are two on each lap, I pour a cup water down my back or over my head. I don't really need to drink any of it. I've taken the occasional cursory glance at my watch but I'm not paying it too much attention. There are kilometre markers but I'm not really sure how far each lap is as I don't know how long the opening out and back section was. I'm guessing they are about 4.5Km. I'm just dividing the pace up as usual - when I'm halfway round the third lap at the start of the causeway I'm looking forward to the final lap, on the final lap I'm looking forward to the causeway and once on the causeway I'm thinking of the final curve to the finish. I've got a 2012 photo of me coming round the curve and I know no matter how tired I am I'll be enjoying that moment. But mostly I try not to look ahead at all, just be in the moment and concentrate on the usual breathing, relaxation and form.

The final curve arrives and I've finished in 1.46.51. It's over eight minutes slower than 2012 but I've given it all I had. It's fun if a little sobering comparing photos from both years taken in almost exactly the same place on the run in.