The period of Bharhut stupas is:-

The correct answer is 'Shunga period.'Key Points

• A stupa was a large hemispherical dome with a central chamber in which relics of the Buddha or some Buddhist monk were kept in a small casket.
• The base was surrounded by a path for clockwise circumambulation (pradakshina), enclosed by wooden railings which were later made in stone.​
• The Bharhut stupa in its present form dates to the middle of the second century BC during the Shunga period.
• It is important for its sculptures.
• Its railings are made of red stone.
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Thus, The period of Bharhut stupas is Shunga period.