Kirstenbosch Botanical Gardens

Kirstenbosch is an absolute must see for anyone visiting Cape Town. It is a beautiful public garden perfect for a quiet stroll or a picnic with friends and family.

here is some interesting info about Kistenbosch courtesy of Wikipedia:

The garden is one of eight National Botanical Gardens covering five of South Africa's six different biomes. When Kirstenbosch, the most famous of the gardens, was founded in 1913 to preserve the country's unique flora, it was the first botanical garden in the world with this ethos. Furthermore, what makes the Gardens so famous worldwide is that (with minor exceptions) only indigenous plants are cultivated.
The garden includes a large, indoor greenhouse exhibiting plants from a number of different regions, including savanna, fynbos, karoo and others. Outdoors, the focus moves to plants native to the Cape region, highlighted by the spectacular collections of proteas. Kirstenbosch enjoys great popularity with residents and visitors. From the gardens several trails lead off along and up the mountain slopes and these are much used by walkers and mountaineers. One of the trails, up a ravine called Skeleton Gorge, is an easy and popular route to the summit of Table Mountain. This route is also known as Smuts' Track after Prime Minister Jan Smuts who used this route regularly. On the slopes above the cultivated parts of the garden a contour path leads through forests to Constantia Nek to the south. The same contour path can be followed to the north for many kilometres and it will take the hiker past the Rhodes Memorial to the slopes of Devil's Peak and beyond.
Kirstenbosch regularly exhibits Zimbabwean stone sculptures in the gardens. Many of the artists are associated with Chapungu Sculpture Park in Zimbabwe.
In summer, a popular series of outdoor concerts are held in the gardens on Sunday evenings.

If you are interested in going on a guided tour of Kirstenbosch check out these Cape Town Tours