Xi'an combines ancient walls, evening streets, and nearby mountain views more richly than many first expect.
Late afternoon to dusk is the best time to walk or cycle and watch the old city lights come up.
The wall loop is long, so you do not need to complete the whole circuit. If energy is limited, choose the gate that fits your route and go up around dusk. On windy or hot days, a short walk can feel better than committing to a bike ride.
The plaza and surrounding area feel livelier after dark, especially when the evening crowds gather.
The Big Wild Goose Pagoda area is lively at night, but crowds rise with the energy. Pair dinner, the plaza, and nearby streets in one evening. Avoid pushing late into the night right after a Terracotta Warriors day, because the fatigue carries into the next morning.
Terracotta Warriors and Huashan both justify an extra day, though they ask very different energy levels.
The Terracotta Warriors and Huashan are both outside the city, but they are not interchangeable. The warriors are about history and guiding; Huashan is about stamina and weather. With only four days, protect the warriors first and save Huashan for a longer version.
After this theme, return to the overview for the other entry points, or place it inside a route that fits your trip.