Have done this 4 times and used road shoes, even the one year when it was very wet and muddy. Obviously it's fairly flat except for the bridges (quite a lot of them!) and they tend to be concrete/tarmac so on the whole grip isn't a problem.
I'd agree with Meadower. Edinburgh is a great city but if you want to run a Scottish marathon then I think Loch Ness is miles ahead.
26.46. Seem to have visited a few offices in Canary Wharf.
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