Trains on the East Coast Main Line were brought to a virtual standstill after a man was hit and killed by a train at Tuxford West Junction.
The incident caused trains between Doncaster and Grantham to be delayed by up to 60 minutes on Monday morning.
Many of the trains travelling along the East Coast between Leeds, York and London Kings Cross were cancelled.
The incident happened at around 8.40am, and police and ambulances attended.
However, the man was declared dead at the scene.
Free WiFi was activated on all Virgin Trains services for those stuck on trains.
Normal services resumed at around lunchtime on Monday.
British Transport Police say they do not believe the incident to be suspicious.
