I got a question for you: Telecommunications in India began with the introduction of the telegraph. The Indian postal and telecom sectors are one of the worlds oldest. In 1850, the first experimental electric telegraph line was started between Calcutta and Diamond Harbour. In 1851, it was opened for the use of the British East India Company. The Posts and Telegraphs department occupied a small corner of the Public Works Department, at that time.

Answer this question: when was first telegraph line started in india?
Let's think first:
The relevant information is: In 1850, the first experimental electric telegraph line was started between Calcutta and Diamond Harbour.
Therefore, the answer is 1850.