Norway’s Secrets of the Ice team reported in September that it had recovered 48 prehistoric arrows that year from melting mountain ice in Jotunheimen. Some slate arrowheads and wooden shaft remains are estimated at 5,000–6,000 years old by comparison with earlier finds; that age does not apply to all 48 arrows. Ice preserves wood, hide, and textiles, but they decay rapidly after exposure. Since 2006 the team has recorded 73 sites and more than 5,000 artifacts, and it expects many studied ice patches could disappear within 20 years. More discoveries therefore also mean a narrowing window for rescue fieldwork and conservation.