Guild of Venturers founded in Númenor
Event Type: General
Age: 2nd Age - Pre-Rings
In the thirty-ninth year of his age Aldarion returned to Númenor, bringing gifts from Gil-galad to his father; for in the following year, as he had long proclaimed, Tar-Elendil relinquished the Sceptre to his son, and Tar-Meneldur became the King. Then Aldarion restrained his desire, and remained at home for a while for the comfort of his father; and in those days he put to use the knowledge he had gained of Círdan concerning the making of ships, devising much anew of his own thought, and he began also to set men to the improvement of the havens and the quays, for he was ever eager to build greater vessels. But the sea-longing came upon him anew, and he departed again and yet again from Númenor; and his mind turned now to ventures that might not be compassed with one vessel's company. Therefore he formed the Guild of Venturers, that afterwards was renowned; to that brotherhood were joined all the hardiest and most eager mariners, and young men sought admission to it even from the inland regions of Númenor, and Aldarion they called the Great Captain.
Unfinished Tales, Part 2, Ch 2, Aldarion and Erendis
When six hundred years had passed from the beginning of the Second Age Vëantur, ... first achieved the voyage to Middle-earth. ... Thereafter seafaring became the chief enterprise for daring and hardihood among the men of Númenor; and Aldarion son of Meneldur, whose wife was Vëantur's daughter, formed the Guild of Venturers, in which were joined all the tried mariners of Númenor....
Unfinished Tales, Part 2, Ch 1, Description of the Island of Númenor