The path up to the castle is steeper than I remembered. The chestnut trees are shedding their leaves like worn-out musical notes, yellow and rust-brown, and the autumn wind carries the scent of damp earth and wet sandstone down the slope. Heidelberg lies below me, the city squeezed between river and rock, the bridge its stony backbone—and beyond, the Neckar, sluggish and silvery-gray like an old mirror.