Gimlet's portals

These were two unnamed portals, constructed by the rock gnome pirate Gimlet Watersprecht some time in the 1370s DR with aid of a small crew, that formed a pirate trade route between the Inner Sea and Trackless Sea. Both portals were constructed to not allow entry by large ships and the key to activating them was casting any spell in the Illusion school of magic.

Location
One of these portals was located in the Trackless Sea, about a day's journey east of Lantan. There it was situated between two tall immovable rods that were  apart. These immovable rods were of a blue metal, identical in coloration to their surrounding water, making them barely visible to even those who knew about them. The activation buttons of these immovable rods were capped with metal hoods and fused into place, ensuring that they would not be deactivated.

The other portal was located within the a low yet wide, half-submerged cave of a small, uninhabited isle in the Pirate Isles of the Inner Sea. The cave was just large enough for a rowboat or narrower keelboat to fit through, though creatures taller than the average halfling or gnome had to duck, and behind the portal was the end of the cave.

History
Following his construction of these portals, Gimlet began a quite lucrative operation of trading firearms to the Pirate Isles and raking in treasures from the nations that stood along the shores of the Inner Sea. The former activity notably caused a strong decrease in business for the pirates of the Nelanther Isles.

Notable Inhabitants
The portal on the Lantan side was guarded by a tojanida, who Gimlet had recruited to be part of his "crew".