The best time to hike in Asia depends on the region. In Nepal, the trekking season runs from September to May – but you may wish to time your trip to coincide with the rhododendron flowering in the Annapurnas (March and April) or to see Everest Base Camp in preparation for the climbing season (April and May).
In Kyrgyzstan, the window is a short summer season from June til early September, whereas in Japan you should avoid these dates as the humidity is intense, and instead aim for Sakura cherry blossom (spring) or the fall foliage (autumn).
The best time to visit China for trekking depends on the region you're exploring, but generally, spring (April to early June) and autumn (September to early November) are ideal across most of the country. As for Sri Lanka, December to March are best for the central highlands (including the Knuckles Range and Adam's Peak), as well as July to September.
Vietnam has three climatic zones with different seasons just in one country! We suggest reading the climate and country guide for each trip and using this to make your decision, or asking one of our friendly sales team what your best option is.