get the church tower and duplicate and place the part of the church with the door in the middle. connect the beam.
step 2 of 8
clone some texture to fill the gap and erase some part of the tower.
step 3 of 8
duplicate the gate structure twice and place them as walls
step 4 of 8
duplicate the gate structure again and scale it up a little. replace the door w/ a large window. get other parts from the source image and arrange them accordingly.
step 5 of 8
get the triangular part and use them to make the top of the towers.
step 6 of 8
i use brush tool to create the flag. then place the tree from the source image and added knights on the wall.