Koyo means autumn colors, and momijigari, literally autumn leaf hunting, is the name for the Japanese habit of taking trips specifically to go look at them. For a few weeks each year, mountainsides, temple gardens, and city parks turn deep red, orange, and gold, and people plan entire outings around catching it at its best.
The tradition goes back to the Heian period, over a thousand years ago, when court nobles in Kyoto wrote poetry and held gatherings centered on the changing leaves, much as they already did for cherry blossoms in spring. What started as an aristocratic pastime slowly spread to the rest of the country and had become a widely shared seasonal custom by the mid-eighteenth century.
Koyo often gets described as the autumn answer to hanami, the spring cherry blossom viewing that tends to get more attention internationally. The two traditions share the same basic spirit, dropping everything to go admire a tree for a few days before the moment passes, but koyo tends to unfold at a slower, less crowded pace and lasts longer in any one place.
Japan even tracks the autumn colors the same way it tracks cherry blossoms, with a koyo forecast that follows a color change front as it moves down the country. It typically begins in the mountains of Hokkaido in late September, then works its way south through the Tohoku region and central Japan before reaching Kyoto and Tokyo in late November or early December.
Some of the most famous viewing spots turn into genuine events, with temples and gardens in Kyoto lighting up their maple trees after dark for nighttime viewing, and specific mountain roads and river valleys drawing steady streams of visitors purely for the view. Roasted chestnuts, sweet potatoes, and maple themed snacks show up everywhere as the unofficial food of the season.
Part of what makes koyo resonate is the same quiet idea behind cherry blossoms: something this beautiful is only going to last a short while, so it is worth stopping to actually look at it. Rather than being sad about that, the tradition treats it as a reason to slow down, get outside, and enjoy a season that is doing something spectacular right in front of you.