We will be in London next month and just discovered that the London Marathon is happening on Sunday April 26 with 100K runners. Our hotel is very close to Tower Bridge so it will be easy to cheer on the runners but moving around the city may be more challenging.
Plan on visiting the Tower of London during the morning of the race and avoid the crowds around the city. Within 6 hours the race will be over and by then the crowds should be thinned out.
The race has a rolling start with an 8 hour finish requirement. The finish line closes at midnight. Tower Hill is mile 23. It’s going to be an exciting time to be in the city just not for the traditional sights. I’m glad that it’s not my first time.
That number is somewhat of an exaggeration. Last year there were a record 57,000 runners and this year will be similar. There is some current talk about future events being spread over two days rather than one, which would mean around 100,000 runners.
There will be difficulties in walking around where the route is and obviously bus routes will be disrupted but the tube will by and large run fine (with a few pinch point stations). You should either go with the flow and enjoy the event as spectators or plan to get to tourist sites sway from the route where you will be fine.