The thimbleberry is the bright scarlet, cap-shaped aggregate fruit of Rubus parviflorus, a soft, thornless bramble of North American woodland edges and mountain slopes. Built like a shallow, hollow raspberry from a cluster of small drupelets, it ripens from firm pink to a deep, velvety crimson and tastes intensely tart-sweet with a fragrant, jammy berry perfume. Too fragile to ship or store, it is almost never sold fresh and is prized above all for a celebrated wild jam of the Great Lakes and Pacific Northwest.