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Reason for naming Circar Express:
7643/ 7644 Chennai Egmore – Kakinada Port (SCR Hyderabad division – RSA with
7651/ 7652 Chennai Egmore – Kacheguda Express)
The Northern Circars was a former division of British India's Madras Presidency, which consisted of a narrow slip of territory lying along the western side of the Bay of Bengal in the present-day states of Andhra Pradesh and Orissa....
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The territory derived its name from Circar or Sarkar, a term applied to the component parts of a subah or province, each of which is administered by a deputy governor. These Northern Circars were five in number, Chicacole (Srikakulam), Rajahmundry, Ellore (Eluru), Kondapalli and Guntur. After changing hands frequently between the Bahamani Sultans, the Mughals, the Nizams of Hyderabad and the French, the British finally took over in 1768.