Oblivion Remastered has been well-received by the gaming community. It maintains the same Elder Scrolls charm while adding visual updates and quality-of-life tweaks. There have been several bug fixes, from audio issues to environment clipping. The game also retains its former quests, and this guide will show you how to complete Lifting the Vale.
How to Start the Quest (& Reach Pale Pass)

After hitting fame level 10, you will hear talk of Akaviri artifacts in Bruma among the NPCs. Talk to someone about it, and they ask you to speak with the Countess of Bruma’s herald, Tolgan. Go north on the world map to locate the region and talk to him. He wants you to meet his Countess, Narina Carvin, inside her castle. He then gives you 25 gold as a stipend and informs you that the Countess can only be met between 8 a.m. – 6 p.m.

Head inside the castle and talk to her. She tells you that as an antique artifact collector, she is interested in a certain Akaviri antiquity to complete her collection — The Draconian Madstone. She then describes the stone as “a snake coiled around, encircling itself”, and its last known location at Pale Pass. Finally, she gives you a map and a key that supposedly belong to an Akaviri messenger.
How To Complete the Lifting The Vale Quest

You must retrieve an Akaviri artifact and return it to the Countess to finish the quest. According to the map, the first location you need to visit is the DragonClaw Rock. It is a snowy mountain east of the region of Bruma. Once you reach here, open up the diary and turn to day seven for the next landmark.
The Sentinel

The diary mentions ‘following a narrow path to the west’. Head northwest from the entrance, and continue towards the snow terrain. After a while, you will reach the second landmark: The Sentinel. It is a giant statue of a knight holding a sword. Refer to the diary for the next landmark.
Serpent’s Trail

Follow the same path until you see a door that takes you to Serpent’s Trail. However, be cautious as a Troll, a bear, and a Spriggan are wandering nearby. Inside, traverse the caves, and you will eventually come across the remains of the Akaviri messenger. Interact with the stone tablet in his hand, which has mission orders written on it. Fight ahead through ogres, wolves, and rats to reach the end of the cave with another door. This one takes you to the Pale Pass.
Pale Pass

Continue down the only path available until you reach the fort. Head inside and turn right into the door that takes you to the Mouth of the Serpent. This dungeon is filled with undead enemies and contraptions, so watch your step. Proceed to the Scales of the Serpent, and then another dungeon called the Fangs of the Serpent. Fight through to finally reach the last one called the Womb of the Serpent. You will see the Akaviri commander Mishaxhi waiting to meet you here.

During your conversation, hand him the orders you picked up earlier. He is content with your work and is finally at peace. A wall opens up in front of you, which has the Madstone inside on a pedestal. All that’s left now is to return to the Countess and give her the artifact. Speak to her and she will be pleased, rewarding you with the Ring of Vipereye — an item that fortifies agility and grants magic resistance.
Note: If you failed to pick up the tablet, the other options make the commander hostile, and you need to defeat him to open the secret passage.
There is a similar involved side quest that gives you a pretty interesting Daedric artifact, check our guide here on how to complete the Sanguine quest in Oblivion Remastered.