Adelphi (Greek: adelphoi, "brothers") is a district of London, England in the City of Westminster. The small district includes the streets of Adelphi Terrace, Robert Street and John Adam Street.
The district is named after the Adelphi Buildings, a block of 24 unified neoclassical terrace houses that occupied the land between The Strand and the River Thames in the parish of St Martin in the Fields, which also included a headquarters building for the "Society for the Encouragement of Arts, Manufactures and Commerce" (now generally known as the Royal Society of Arts).
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