They are stacked up for lanbding, flying in an oval - the bottom one is cleared for approach, and the stack moves down.
The bottom of the stack is 3-4,000' above ground - with 2,000' spacing above each.
They try not to do this anymore as it wastes fuel - that is why they close the door on the plane, pull away a few hundred feet, and sit there.
Basically you are in a hold waiting for an arrival slot to open, maybe 8 hours away!
One thing we do see around here is planes lined up on approach - they are usually spaced about 10 miles apart, doing 250knts (about 5 miles per minute)
That leaves a couple minutes between landings.
Because there is no relative movement between them, it sometimes seems like they are hovering.