But all is not lost … there are plenty of great places to run that escape the worst of the heat. Here are my favourites:
Sure there are hills that will make the heart rate crank on top of what the atmosphere is already demanding from your run, but the shade you will get from the ample supply of trees (and the pergola) definitely makes this a top running destination for a hot day.
The added bonus of course is the cool waters of multiple bathing ponds and the Lido just near Parliament Hill Track.
Green Park & Victoria Park
The centre of London is often a few degrees warmer than the suburbs (a combo of the concrete holding the heat and being in a valley), so if you can't escape to the 'burbs, Green Park and Victoria Park are probably your best bet for hunting out the shade.
Russia Dock Woodland
For another central city option, just south of Tower Bridge, run 1mi east (following the shade of the Bermondsey's Thames Path) through to Southwark Park and on to Greenland Dock and the shaded Russia Dock Woodland. Tip: There is a water fountain just up from the Mixed Bathing Pond on the way to the Viaduct.
Mid-summer is about the only time of year when Wimbledon Common's boggy trails might actually dry out! When it's hot many runners prefer Wimbledon Common over neighbouring Richmond Park. And if you feel particularly desperate, you could always cool off with a quick dip (read: mud bath) in Beverley Brook (western fence line of Wimbledon Common). (Note: I have no idea if swimming in the brook is even allowed, so better check first!) The main downer is that the only place for refreshments is at the Windmill.
If you need to run long and stay under constant cover of tall, shady trees, look no further than Epping Forest.
Pack some fluids and take the Tube up to Epping. Then run the 15mi back south to Manor Park Station. Get refreshments on the way at High Beach Visitor's Centre and Queen Elizabeth's Hunting Lodge.
Thames Path: East
Water is a great temperature regularity. So the bigger the body of water you are next to, the more temperate will be the weather.
The biggest body of water in London is easily the expanse of the tidal Thames east of Greenwich. Follow the south bank of the Thames Path for 13.3mi all the way around to Erith (follow the barge symbol as opposed to the usual Thames Path acorn). Tip: this is a long run without refreshments or water fountains, so carry your own fluids.
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