Some see Mr. Sharon as the immovable obstacle.
The immovable obstacle for Hearn and snooker is that players need to have silence when they take their shots.
The hedgehog is not supposed to be an immovable obstacle because of its size or weight.
He stood like an immovable obstacle against which no pressure could avail; an embodiment of what Arthur most shrank from believing in--the irrevocableness of his own wrongdoing.
And now that great hideous and immovable obstacle to my plan is no more.
He threw himself downward and tried to wriggle back, but his head struck an immovable obstacle.
He stood like an immovable obstacle in front of his younger brother.
It split cleanly in the middle and its two halves opened wide as they roared past the immovable obstacle.
This wasn't 'The Wall', the immovable obstacle.
Raised lifts cannot be lowered at their base and become immovable obstacles at ground level.