An Oathgate is an immense fabrial capable of transporting anyone to Urithiru. The exact nature of Oathgates is unknown and they are widely thought to be a myth by the people of Roshar.
In the distant past, Oathgates were located throughout Roshar and were the means by which the Knights Radiant traveled from various locales to Urithiru, where the orders of the Knights Radiant were centered. With their betrayal of humankind on the Day of Recreance, over time, the Oathgates ceased to function, whether from lack of use or lack of necessity isn't known, though Shallan thinks that they may have been sealed.
The only known functioning Oathgate on Roshar is capable of transporting massive numbers of people from Stormseat (the former capital of Natanatan), called Narak by the Parshendi, at the center of the Shattered Plains, to Urithiru, which is located within the mountains south of the Purelake in the center of the continent.
Just why this Oathgate is still operational or hasn't been sealed isn't known, but such was suspected by Jasnah, who researched its history and imparted her suppositions to her ward, Shallan, who then followed up on her mentor's research and found it to be functional.
Prior to this novel's end, many teleportations of former residents within the various warcamps of the Highprinces have taken place and most Alethi, formerly in the Shattered Plains, are now ensconced in Urithiru (though they don't really know this or the legendary city's history). What they know is that they're safe from the Parshendi ... but the Everstorm looms.
When Navani writes something via spanreed to Thaylen City from the control building of the Oathgate to that city within Urithiru, the building itself flashes a moment later - a ring of Stormlight running around it, like the afterimage of a firebrand being waved in the dark.
She observes that, with the help of a Radiant on either end, paired Oathgates across Roshar will be able to be unlocked and utilized.
The Oathgate at Narak is a perfectly circular plateau amongst the jagged and broken plateaus about which it is surrounded, which were created by some sort of disaster. It is obvious to both Shallan and Renarin that this plateau already existed before the disaster and that when it occurred, the plateau remained.
|“||"On the old maps it was a raised section, like a giant pedestal. When the Plains were broken, it remained this way."||”|
–Shallan to Renarin
The control building at the center of the platform of the Oathgate at Urithiru to Thaylen City is described as being shaped like the others - mosaics on the floor, keyhole mechanism in the curved wall. The patterns on the floor, however, are glyphs in the Dawnchant. This building is identical to the one in Thaylen City - and, when engaged, will swap places with that one.
The glyphs on the floor indicate that that it might be possible to transport directly from one city to another without coming to Urithiru first.
The control mechanism to this Oathgate is a keyhole, which is in the center of a ten-pointed star on a metal plate. Navani confirms that it is the same as the one to the Shattered Plains.
In Thaylen City, the platform that surrounds the Oathgate there has been turned into a sculpture garden ... but most of the sculptures lay toppled and broken. Still, it is high up in the city and gives an excellent view.
Access and LocationsEdit
It is also known that nine of the ten Oathgates have been sealed, though by what means or by whom remains unknown.
It isn't yet known just how it might be possible to transport directly from one city to another without coming to Urithiru first. For now, each gate can swap only with its twin, and they have to first be unlocked from both sides by a Radiant.
Further, the greater the number of people to be teleported in a single attempt, the more Stormlight is required.
|“||"Transferring only the control buildings, instead of the entire platform, should save us Stormlight."||”|
The only way to use an Oathgate is to infuse the gemstones located within the center temple of the gate with Stormlight and use a Shardblade to direct where one wants to go. Shardblades bonded to dead spren, however, do not work.
When Malata inserts her Blade into the keyhole of the gate in Urithiru, the metal of the plate therein shifts and flows, matching the shape of the Blade. As she pushes against the side of the Blade's hilt, the inner wall of the control building rotates. The floor underneath the mosaics glows, illuminating them like stained glass. She then stops her Blade at the proper position, and - a flash of light later - she and Dalinar arrive at the platform in Thaylen City.