imperial staircase

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double return stair, side flights

double return stair
A stair having one flight from the main floor to an intermediate landing and two side flights from that landing to the floor above.
References in periodicals archive ?
The best and most congenial part of the building is the imperial staircase which rises, beyond round arches, from the entrance hall (and behind which now stretches the arid space of the Ondaatje Wing with its giant escalator).
Marbled pillars frame the oak imperial staircase that leads to a half landing before dividing in either direction, ?
Any redevelopment scheme must be approved by the Welsh Assembly Government's historic environment agency Cadw, which has already ruled that the facade and imperial staircase must remain a feature.
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