About 35 minutes.
London, Euston and London, Victoria both have underground stations on the Victoria Line.The journey time is about 8 minutes.
About 25 minutes by cab.
About 4h15 by changing at Banbury and Princes Risborough. About 4h05 by changing at London Euston and London Marylebone.
Take the tube to London Euston and get a train from there.
It would take about 1 hour to walk from Euston to Buckingham Palace.
Take a South West Train service to Vauhall and then change onto the London Underground Victoria Line which will take you to Euston.
The quickest way is to take a train from Euston Station.
Trains don't go from Kings Cross to Manchester. They leave from London Euston which is a 10 minute walk from Kings Cross. The journey from London Euston to Manchester Piccadilly takes around 2 hours 10 minutes.
The London Underground is the best option. Take the District Line to Edgware Road before taking the Circle Line to Euston Square.
About 15 miutes by cab or 45 by public transport.
About 30 minutes
About 20