The Summer Palace is built around water, and the water is not decoration - it is most of the site. Kunming Lake occupies roughly three quarters of the park's area, with Longevity Hill rising on the northern shore and the Seventeen-Arch Bridge and South Lake Island closing the southern end. Walking the perimeter is one way to see it; getting out on the lake is another, and it changes the whole experience, because from the middle of the water you see the palace as it was designed to be seen, as a composition of hill, roof lines and water rather than a sequence of gates.
What the lake is
The lake is artificial in the sense that it was enlarged and reshaped. It began as a smaller natural sheet of water fed by springs at the foot of the hill, and in the eighteenth century it was dredged and extended to its present size, its excavated earth used to raise and shape Longevity Hill. It was given its present name after a lake in the old imperial capital at Chang'an. The western shore was left deliberately open, planted with willows and spanned by the long Seventeen-Arch Bridge, so that the view west would look like the water gardens of the lower Yangtze rather than the suburbs of a capital.
Getting on the water
Several kinds of boat work the lake. There are covered dragon boats that run scheduled crossings, usually between the eastern shore near the palace gates and South Lake Island, and pedal boats and small electric boats for hire at a couple of jetties. The crossing to South Lake Island is the one worth taking: it lands you at the island's temple and puts you at the foot of the Seventeen-Arch Bridge, from which you can walk back east along the causeway or take the same boat back. The boats are seasonal and stop when the lake is closed by ice, which in a normal winter is from around December to March.
Practical notes
Boat tickets are sold separately from the park entrance and are bought at the jetties rather than in advance; queues are longest in the middle of the day in summer and on autumn weekends. Mornings are calmer and the light on the hill is better. If you only have an hour on the water, take the crossing to the island and walk back over the bridge - it covers the best of the southern lake in one loop. The park itself needs a timed reservation bought in advance through its official channel, and the boat jetties take cash or a mobile payment app rather than foreign cards.
