Ueno Tōshō-gū

This shrine honours Tokugawa Ieyasu, the warlord who unified Japan; it's the (much smaller) Tokyo counterpart to Nikkō's grand Tōshō-gū. Resplendent in gold leaf and ornate details, it dates to 1651 (though it has had recent touch-ups). The exterior alone is impressive, if you want to skip the admission fee. Throughout January and February, the shrine opens its spectacular peony garden (combined entry is ¥1100).