This keep of the Ebonheart Pact does not show any remains in the era of Oblivion. The only possible link is Lake Arrius. Which is located north of Cheydinhal.
Yet again, Blue Road Keep is non-existant in the time the Oblivion crisis takes place. The road leading from the Imperial City to Cheydinhal is called The Blue Road, but that is the only reference to this keep.
This keep is located on the western side of The Reed River in ESO. It is the most southern home keep of the Ebonheart Pact. In Oblivion the remains of the keep are not to be found. Instead we find the settlement of Drakelowe. It is a tiny settlement, only containing one house and only one habitant called Melisande.
Located east of the Temple of the Ancestor Moths, Kingscrest Keep is the most northern home keep of the Ebonheart Pact. Remains of this keep are not found on the Oblivion map.
An outpost in ESO, but a medium-sized fort in Oblivion. Located south from Blue Road Keep it seems to have moved location for gameplay purposes. The remains found in Oblivion are located far more to the east than in the online version.
A fort in both version of Cyrodiil. However the location of Fort Ash in the Online version seems to be at nearly, if not exactly, the same location of Fort Nikel in the Oblivion version. Which obviously was done for gameplay purposes.
Once a magnificant keep in the Alliance War, only a small town or village in the Oblivion game. The town or village consists of only two houses. This wasn't always the case. Aleswel once was a large village but all villagers were evicted on pain of death by Grand Warlord Dortene of the Daggerfall Covenant. There are no remains of the fort to be found in the Oblivion game.
The most northern fortification in The Elder Scrolls Online, only a rock in The Elder Scrolls IV: Oblivion. At this location the road looks like a dead end. However a road leads to the east, eventually leading you to the Serpent's Trail and Pale Pass. It ends at Fort Pale Pass, the entry way into Skyrim which we visit in the Elder Scrolls V: Skyrim.
Fort Glademist was abandoned after the Alliance War. Nothing remained of the fort and the only references one can find in the Oblivion game is the fact that it is located in the Glademist Fields area. In which Glademist cave is located, a cave network used by the Blackwood Company.
No remains can be found of this fort in Oblivion. It probably was abandoned after the Alliance War, neglected and has fallen into ruins.
This outpost is located between Chalman Keep and Fort Aleswell. The village of Bleaker's Way was first settled by Ulf the Bleaker. In the times of the Alliance War, the villagers were ordered to leave the village. Those who refused would be punished with death. During the war giants occupied the village. In Oblivion the village was reclaimed by men. There are no remains of Bleaker's Outpost in Oblivion.
The only remains of Castle Brindle in Oblivion is Brindle Home. Which is a village located between Chorrol and Skingrad. The location of Castle Brindle relative to Brindle Home seems to be far more south, probably for gameplay purposes. The castle seems to be located near The Gold Road, which connects Skingrad with the Red Ring Road around the Imperial City.
There are no remains of Castle Bloodmayne in The Elder Scrolls IV: Oblivion. The only reference that can be found is Bloodmayne Cave, which also is a delve (mini-dungeon) in ESO.
Castle Faregyl is a key location of the Aldmeri Dominion. The castle can not be found in the Oblivion. Instead we find Faregyl Inn, located west of The Green Road which leads from the Imperial City to Bravil. No remains of the castle can be found which was located on the east side of The Green Road.
The castle of Roebeck is located perfectly on the map. However in Oblivion the castle is located near the White Rose River. This river could have formed after the era the Alliance War takes place in, because nothing of this river can be found in the Online version. There are some bridges to be found that cross dried up riverbanks. This could be the White Rose River.
An outpost located south of Fort Ash and north-west of Castle Roebeck. In Oblivion we find the remains of this outpost in the form of a small fort. The location of Nikel is the most noteworthy. In Oblivion it is located next to the bridge leading into the Imperial City, west of the village of Weye. In the Online version the outpost is located far more south, near Fort Virtue on the Oblivion map.