After the worst-ever Mount Everest disaster killed 16 Sherpa guides earlier this year, climbing season was cut short—but even getting to base camp can be deadly. A 49-year-old British woman who was trekking in the region died in her hotel room after returning from the camp, which is 17,700 feet above sea level, the BBC reports. The woman, who was trekking with her daughter, had complained of breathing difficulties. "She possibly died of altitude sickness," a local police official tells AFP. "Her body was airlifted to Kathmandu for a post-mortem." (Before the window for climbing the mountain closed in May, two women hired a helicopter to bring them past the danger zone where an avalanche killed the Sherpas.)