Eight-year-old Pune lad Kaustubh Vemuri Wednesday successfully swam the 71-km stretch from the Gateway of India to Dharamtar Jetty and back in 17 hours and 30 minutes.

The fourth standard began the swim Tuesday afternoon and finished the gruelling feat at around 9:30 Wednesday.

Vemuri was helped by his coach Vinay Marathe in achieving the feat.

The event has been recognised and was organised by the Pune District Amateur Aquatic Association and the Maharashtra Amateur Aquatic Association.