Tar-Aldarion was the sixth of the Kings of Númenor. He had only one child, a daughter of great beauty named Ancalimë. In her favor he changed the Númenórean laws of succession so that if there was no eldest son, the eldest daughter could inherit the Sceptre.

There were then three Ruling Queens of Númenor, though there would have been four had Tar-Míriel (also known as Míriel or Ar-Zimraphel) been allowed to take the Sceptre as was her right.
Encyclopedia entry originally written by Nienna-of-the-Valar