Spring (late March to May) is the finest season: cherry blossoms line the paths between the tomb mounds and around the temple precincts, the weather is mild, and the light for photography is superb. The Gyeongju Cherry Blossom Festival in April draws large crowds but the city handles them better than many Korean destinations.
Autumn (October–November) is the second best period, with maples turning red in the mountain temple valleys. Summer is hot and humid; the city is still very much worth visiting but prepare for the heat. Winter is cold but clear, and the city sees far fewer visitors — Bulguksa in light snow is particularly beautiful.
The Gyeongju Historic Festival in late September or early October features traditional performances, archery, and cultural events tied to Silla history.