The Swing Bridge

Hydraulic power is still used to move the bridge, derived
from electrically driven pumps.  These feed a hydraulic
accumulator sunk into a 60 foot (18 m) shaft below the
bridge; the water is then released under pressure which
runs the machinery to turn the bridge.  The mechanism
used for this is still the same machinery originally installed
when it was built.  The bridge, a Grade II* listed structure,
stands on the site of the Old Tyne Bridges of 1270 and 1781,
and probably of the Roman Pons Aelius.

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Tyne Swing Bridge
Pons Aelius