When Keith Stewart opened his Pezula Resort, in Knysna, South Africa, in 2004, he hoped for a flood of guests. Instead, he got a flood. At Christmastime, rain gushed through the chimneys, turning the $20 million resort into a swamp. Things have gone more smoothly since. In the past four years, Pezula has won four environmental awards, and last December the resort opened two castles on the Indian Ocean. One of the castles' first visitors was Nelson Mandela, but Pezula also welcomes less illustrious guests. On a hike through the property's 4,450-acre reserve last fall, I spotted a fish eagle on the way to the Noetzie River, where a canoe awaited. Though Pezula feels like a spa set within a tropical forest, it's just minutes from the town of Knysna, where July 4 marks the start of the 25th annual oyster festival—ten days of bike races, music, and shellfish (oysterfestival.co.za). Doubles from $550; pezularesorthotel.com.