The outlets were at the same level as the base of the presumed original roof, and their purpose was to remove rainwater which otherwise would have been trapped inside the keep.
(The outlets; were; at the same level as the base of the presumed original roof) (their purpose; was; to remove rainwater) (rainwater; would have been trapped; inside the keep)
The outlets their purpose rainwater
were was would have been trapped
at the same level as the base of the presumed original roof
to remove rainwater
inside the keep