HORSE GUARDS PARADE (n.) Large open space that doth display horses and those bedecked men who guard the equine animals against peril.
Dr. Johnson’s London Dictionary for publick consumption in the twenty-first century avail yourself on Twitter @JohnsonsLondon
CabbieBlog 
In the Met, we always called it ‘The Dust’.
Cheers, Pete.
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That makes sense, it must be pretty awful standing on the Parade on a hot day b
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