Loop line (railway)
Loop line has several meanings.
A less important line which leaves a main
line and then rejoins it later, continuing in
the same direction. Significantly longer than a
passing...
more... loop , its purpose may be purely to
provide a bypassing route, or it may provide
a goods or passenger service in its own right,
such as the Hertford Loop line.
A configuration, sometimes known as a
balloon loop where trains entering it turn
though a half circle and return to the start of
the loop facing in the opposite direction from
which they came, such as the Sutton Loop.
A totally enclosed system whereby trains
always remain in the loop, as in the London
Underground Circle line.
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