These two UNESCO World Heritage Sites form the twin pillars of any Sri Lanka cultural itinerary – Sigiriya’s 5th-century sky palace rising 200 metres above the surrounding forest on a volcanic monolith, its terraced water gardens, cliff-face frescoes, and mirror wall inscribed with centuries of visitor poetry making it the most architecturally and symbolically audacious site in South Asia; and the five Dambulla Cave Temples whose walls and ceilings have been continuously painted with Buddhist iconography for over 2,000 years in an accumulation of devotional art so dense and layered that it rewards repeated visits. Together, they are indispensable – and together, they can be experienced in a single day if you start early and give Dambulla the afternoon it deserves.