The group steps through the space where a large, wooden gate used to be. Iron hinges hang useless on the wall, the remains of the original wooden gate slowly melting into the ground, covered in moss.
Inside the walls, the courtyard is relatively empty. Tall grass and weeds grow where the sun reaches. Where it doesn't, it's shorter grass, moss, and dirt. Along the wall, an old wooden walkway still clings to the stone. The right, there are two stone columns that support the walkway. To the left, a couple rooms. Probably barracks for the officers stationed here. In the back left corner is the main floor of the tower.
Inside, against the outer wall, there is a dining table and benches. In the far corner, behind the stairwell, was probably the location of a serving nook. Holes in the outer wall were probably used as some sort of pass-through to the outside, where the kitchen was likely located.
On the other side of the stairwell, crates are stacked up. The crates are empty, and look like they were probably supply crates that were brought to the castle and then stored for firewood. Old barrels are stacked on the floor in the nearest corner of the room, . They are mostly empty. One of the barrels, recently turned on its side, has some dark liquid leaking from it into the dirt-covered floor. This would normally be unremarkable, except for the footprints tracking through it towards the stairs.
They match the footprints you've been following.