There are six tall ventilation chimneys pumping foul air out of the tunnel, three on the Liverpool side, and three (including a double one at Sydney St) on the Birkenhead side. Most of the chimneys are over 200ft (62m) high, housing ventilation fans between 40ft and 50ft in diameter.
Below: the George's Dock Ventilating Station, across the Mersey on the Liverpool waterfront. Another tall chimney, but around this one, five storeys of offices were built. The contractor for the project was Edmund Nuttall; yet another Edmund (born over 60 years after the tunnel's opening) stands in shot.
Let's zoom in on some of that lovely Art Deco ornamentation on the upper half of the ventilation chimney. Jazz-age Mesopotamia - electric, wireless and sacred birds. In Portland Stone.
Below: one of the original toll booths, rescued and restored, stands beside the George's Dock Ventilating Station. Green and gold are the colour scheme.
Below: two of the figures that sit, lotus-legged in alcoves - Afro-Asian, transcendental. Sentinels of Empire - or more mystical in meaning?
Below: detail from the railing around the ventilating station. Geometric snakes zig-zag around a flaming staff/spearhead, surrounded by waves. Golden Egyptian wings hover above.
We were delighted that so much of this wonderful architecture has survived to see our day. Most of the Mersey (Queensway) Tunnel is Grade II listed, so it should now last a whole lot longer.
Liverpool is, after London and Edinburgh, Britain's third 'must-see' city - and is now connected by air to Warsaw via low-cost carrier WizzAir.
This time last year:
Behold and See - short story, part II
This time two years ago:
Signs of progress along the S2 - Lotnisko to Puławska
This time five years ago:
Warsaw's walls bear witness