Artemis' Chariot

Artemis' chariot is a chariot used by Artemis. It is made of silver and pulled by four golden reindeer with silver horns. The bridles (reins) of her chariot are made of silver. in The Titan's Curse, it is described as what Santa Claus' sleigh was based upon by mortals.

The Titan's Curse
Artemis calls her chariot after the battle against Atlas to get Percy, Thalia, Zoë, Grover, and Annabeth to a safe place where she turns Zoë into the constellation "The Huntress". She then leaves to attend the Winter Solstice meeting.

The Last Olympian
Percy mentions Artemis in her chariot while fighting Typhon, a monster who broke out a second time and came to help Kronos, Titan Lord of Time, the former king of the Titans before Zeus took over as King of the Gods in the end of the First Olympian War. It is stated that it looks like Santa Claus' sled, except for the fact a girl is driving, and there are silver arrows being shot out of it.

Artemis was the moon goddess because when riding in her chariot the people of Greece thought she was driving the moon across the sky as her brother,Apollo, drove the sun across the sky.

Trivia

 * According to Artemis in The Titan's Curse, mortals got their idea of Santa Claus' sleigh from Artemis' chariot, including the reindeer.