Granny is lady of the lake

Pamela Dickson. Photo / Rotorua Daily Post

A grandmother of 10 has become the oldest person to swim the length of Lake Taupo, finishing the 40.2km journey in 13 hours and 56 minutes on Friday.

Pamela Dickson, 56, trained towards the swim - just shy of a marathon distance - for two years.

"The lake is different from the ocean. There's no tidal assistance, it's just dead water. The wind was hitting me on the side too. The lake is so deep, all I could see was darkness," said Dickson.

She began at 4am at Waihi Bay, near Turangi, and reached the Taupo Yacht Club at sundown, to be met by a crowd of supporters.

"My shoulders were very numb and the whole night I felt like I was rocking. My body was in that rhythm from the water."

Dickson, who works as a massage therapist, has completed 15 Ironman races and holds the record for the oldest person to swim the Cook Strait.

She said she may try Queenstown's Lake Wakatipu next.