Influence of the weather on train services A central question for NS and ProRail is how we can offer reliable transport to passengers, even in extreme weather. The winter of 2015-2016 was fairly mild. Early in January, NS put on ice trains, particularly on the routes to Zwolle, Leeuwarden, Groningen, Deventer and Enschede. These trains scrape ice off of the overhead lines, to reduce the risk of problems with ice accumulation at night. The ice trains are one of the measures taken by NS, ProRail and the other rail companies to enable trains to run according to the timetable during winter weather. We also took measures in the autumn. For example, we used a special gel (Sandite) again this year to combat slippery tracks. Mechanics at the maintenance locations worked 24 hours a day to repair damage to so-called ‘square wheels’. Rolling stock issues meant there were fewer Intercity trains on two routes on a few days in November.To stay alert after three consecutive mild winters and keep knowledge within NS and ProRail on the effects of weather up to date, three joint exercises were held once again in 2016.