In 607 of the First Era, the "Great Crossing" was organized. Emperor Polignac was nearing the end of his reign and wanted to fulfill one of his last dreams: to establish a maritime route between the lands of the central and eastern continents. This was accomplished, and it still exists today, connecting Pamoisard to Khadidja, an essential trading city between the city of sands and the lands of the center. It was called the "Two Islands Way" because of their discoveries during the great crossing. The Islands of Dalryada and Tarra were first discovered at the autumn equinox of the year 607 of the First Era. The first island visited was that of Tarra, and it was also the first to be placed under imperial control despite the opposition and resistance of its local population.

The annexation of the second island, Dalryada, to the Empire was much less straightforward. Very ancient families and clans were established there. These people had always lived off the work of their land and had never listened to any law but their own. There were several bloody skirmishes, but these people were farmers and had to resign themselves to the imperial troops.