Named after Robert Palk, a governor of Madras, the Palk Strait is a strait between the Tamil Nadu state of India and the Jaffna District of the Northern Province of Sri Lanka. With a minimum depth of less than 9.1 m it is 40 to 85 miles (64 to 137 km) wide and 85 miles (136 km) long. Several rivers flow into it, including the Vaigai River of Tamil Nadu.

The unique feature around Palk Strait is that the waves around it, to its north and south are of high contrast. To the north, the waves of Bay of Bengal are mostly swells waves while that on the south, in Palk Bay, are mostly sea waves. Despite being a sea dominated area, the significant wave heights in Palk Bay regions are relatively low. The average significant wave height in Palk Bay close to Adam's Bridge is around 0.5 m.

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