We need to get to Kings Cross from Belgravia area on Sunday morning April 23. The London Marathon is that day. Is traffic on the Underground a problem during that time? Should we just run with the Marathoners? There's an old post with same question, but its the amount of spectators and security I'm concerned about.
Here is the official website you can probably get all your answers when you get there the day before
or by contacting them
https://www.virginmoneylondonmarathon.com/en-gb/event-info/runner-info/
Your route doesn't cross the actual path of the Marathon, but as Emma says use the tube rather than buses.
Thanks for replies. Information is always good..