This is a good quiz question and the answer is under the Museum of London! Underneath the museum of London (which is built on a roundabout) in the bunker-like bowels is a collection of a completely different kind that is not open to the public.
Mortimer Wheeler (1890 – 1976) and Tessa Wheeler (1893 – 1936) were archaeologists who excavated the Roman remains of Verulamium (now St Albans).
Mithraism was a mystery religion centred on the god Mithras. It was practised in the Roman Empire from the 1st to the 4th century CE.