After viewing hugh Stupas in open space in India & Sri Lanka, it is comparatively quite a unique feature to see a Stupa on a building's rooftop. :-)
Bodhi Tree 
Hugh Reclining Buddha, Colorful Wall paintings, Stupa and Bodhi Tree, what a representaion of Sri Lanka!
At the Arrival Hall of Sri Lanka Airport, one will be greeted by the very Serene looking image of Buddha welcoming you to Sri Lanka. :-)
A worthwhile climb, non-taxing with nature scenery along the way leading to beautiful white statue and stupas with beautiful blue sky as contrast. 
Paintings and statues of the Buddha and his life are spread mainly over 5 caves. Although pretty well-preserved, you could still see signs of history in the caves.
2 Hugh Reclining Buddha from 2 different caves with paintings around the surrounding walls of the caves
If without a guide explaining, it will be just another place of interest but with the explanation of the history & rich culture, one better appreciates the art & place better, so always recommended to listen to the guide's explanation before wandering off to take pictures...
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The Samadhi Buddha
Well arranged offerings of flowers on a stone table before the Samadhi Buddha Image.
The interior compound of the temple buildings has a combination of richly carved beautiful inner shrine (left/topmost picture) and more modern (right/bottom picture) Sinhalese architecture. The Tooth Relic (left upper canine tooth) of the Buddha is believed to be housed in the 2 storey inner shrine.
At a connecting tower, one can see the oldest ola leaf book and many other precious leaf book.
There is also a museum in memory of the elephant whom had been carrying the sacred tooth relic during the past yearly festival parade and whom had lived to high age of over 80 years old.
It is a place worth visiting especially during Full-moon day (every full moon day of the month is their public holiday so they have at least 12 days of leave each year excluding other leave entitlement!) where at the garden compound you can see many locals observing the 8 Precepts (their culture to wear all white).
