People play in a fountain at the Museumplein square in Amsterdam. (AFP)

The Netherlands hit a new high temperature record of 41.7 degrees on Thursday, meteorologists said, as a heatwave turned large parts of Europe into a furnace.

The new record was set in the eastern Dutch town of Deelen, the Meteorological Institute said. The day before the Netherlands already saw its previous record of 38.6 degrees set in 1944 broken.

Paris on Thursday also baked in an all-time high temperature over 42 degrees Celsius as a ferocious heatwave smashed records across northern Europe, sparking concerns about public health and new misery for rail travellers.

Trains have been slowed in several European countries to avoid damage to the railway networks and French national operator SNCF urged travellers to delay journeys planned for Thursday.