Naglfar (“Nail-ship”): This is the ship of the dead. It is made from the fingernails and toenails of the dead. This is why it is always necessary to trim the nails of the deceased before burying them, for if this is not done the nails will provide building material for the construction of Naglfar. The completion of the ship-building will be the sign that the end of the world has begun. The sons of Muspell will then travel on Naglfar to join the assault on Ásgarðr.
The ship sails from the east and is packed with forces of evil and chaos, according to the Poetic Edda.
Naglfar is on its way into the battle against the Aesir gods and will arrive on the shores of Midgard, just in time when the Midgard serpent emerges from the sea.
The captain of the ship is the giant Hrym, who brings with him all the legions of the giants, while Loki takes the helm of the fatal ship full of giants. He steers Naglfar over the stormy and cold northern waters, to Vigrid (Norse: Vígríðr), the plain where the decisive battle will take place.
Superstitions have often accompanied ancient people in their daily life. According to ancient Norse beliefs, it was important that no one in the Viking world should die with untrimmed nails. There is one way to delay the ship’s arrival. The ship’s size would depend on how many deceased had been buried with unpaired fingernails.
If someone dies with long fingernails, the surviving relatives of the dead must immediately cut them short before the deceased is laid to rest. Otherwise, their nails will be used to build the Naglfar larger and stronger.
The ancient Vikings believed that this action could significantly delay the construction of the ghost ship and the day of the end of the world.
Mark Bere Peterson’s Hauntings, Urban Legends the Northern Tradition and Southern Witchcraft 