The bunch of trees in the SWish corner would provide 3/4 cover for up to three people for ranged attacks.
The solo tree would provide one person 3/4 cover from ranged attacks.
The building itself provides cover as well.
At the top of the map around 3 squares off the map to the left, a is a broken crane. The crane itself doesn't work but it does have wheels and is 20 feet long by 7 feet wide, any one behind it would have cover, (assuming the crossbow wielding Hobgoblin's on the far side of the bridge don't go too wide) it has bars on the side to help push, those and the wheels would provide partial cover.
The crane also has around 200 feet of thick rope.