FANTASY ISLAND

An heiress lives her Gatsby dreams at her Big Rideau Lake cottage, complete with parties, lobster and champagne

- Iris Benaroia

HENRIETTA SOUTHAM vividly recalls the Edwardian-style fanfare that signalled summers at the family cottage on Ontario's Big Rideau Lake in the '70s. Her father was Hamilton Southam of the Southam newspaper empire, and every day at the lake was a party worthy of Downton Abbey. At the beginning of each summer, they loaded a boat with long dresses and smoking jackets and even had an old-fashioned squishing apparatus to wring out laundry on the island. Upon arrival at the cottage, they devoured cakes and capons. They wore straw boaters and formal gowns and played tennis and croquet. Marlene Dietrich was a guest one time, and a virtuoso opera singer gave private concerts for years. "It was a genteel paradise," says Southam, now the owner and designer of Henrietta Southam Design in Ottawa. "It was a life of privilege. It seems to be all a dream," she says.

The original cottage burned down in 1979, but Southam wanted to continue a more casual version of her family's tradition. In April of 2013, she spotted a rare listing on Big Rideau Lake: a one-acre island with a cottage on it. She didn't wait for her agent to set up a visit. "I'm heading there! I've got a boat on the lake!" she told her. The island was covered in pines, cedar and ironwood trees-and, as a bonus, it was mostly mosquito-free, due to its high, windy setting. Southam paid $495,000 for the island oasis. She's spent each summer there ever since.