Immersive Fort Dawnguard is a complete overhaul of Dayspring Canyon for The Elder Scrolls V: Skyrim. This mod is created by Grantyboy050, is available for both LE and SE, and its file size is 188.6 megabytes.
Immersive Fort Dawnguard adds a whole bunch of new stuff, while staying true to the original feel. The exterior of the fort includes extra fortifications, a main gate, an alchemy tower, a farming area and greenhouses. The interior features a new chapel, a library, a bathhouse and a prison.
The fort will gradually be cleaned and restored to its original glory, while you progress through the quest-line. The interior layout has been edited to match the exterior. Also, all windows are now transparent so you can see from inside.
The modder has included the Just-in-Time lighting, in order to improve performance and eliminate light flickering. He also added occlusion planes and roombounds to improve interior performance.
The Dayspring Farm is a new area that will house the refugees, and provide food to the Dawnguard. The farm will be built near the lake, towards the end of the quest-line. Lastly, all characters have more varied daily routines, and they will interact with the new features and areas.
You can download the Immersive Fort Dawnguard mod from here for Skyrim Special Edition and from here for Skyrim LE. Also, in case you like it, make sure to endorse the mod as it will really help its creator!