It's best to spend a few days in go to dali.

Dali is a tourist attraction with beautiful scenery and a long history. There are many scenic spots and activities worth visiting. Generally speaking, it is better to stay in Dali for 3 to 5 days, so that you can fully experience the customs and culture of Dali.

In Dali, you can visit Erhai Lake, Cangshan Mountain, Three Pagodas, the ancient city and other famous scenic spots, and you can also taste local specialties, such as crossing the bridge with rice noodles, barbecue, fish with Chinese sauerkraut and so on. Besides, you can also take part in some special activities, such as taking a boat tour of Erhai Lake, cycling around Erhai Lake and visiting Bai villages.

If you are also interested in the scenic spots around Dali, you can consider extending the travel time. For example, you can go to neighboring cities such as Lijiang and Shangri-La to explore more natural scenery and national culture.

In short, according to your own interests and itinerary, choose the travel time that suits you.