1. London Kings Cross to Edinburgh Waverley: Approximately 4 hours and 20 minutes.
2. London Euston to Edinburgh Waverley: Approximately 4 hours and 30 minutes.
3. London Paddington to Edinburgh Waverley: Approximately 5 hours and 30 minutes.
4. London Liverpool Street to Edinburgh Waverley: Approximately 6 hours.
These travel times are estimates and may vary due to factors such as delays, engineering works, or peak travel periods. For the most up-to-date information on train times and schedules, it is recommended to check the official websites or apps of the relevant train operators, such as National Rail, LNER, or Virgin Trains.