Ginkgo biloba: The tree survived the atomic bombing, while the castle was destroyed.

Shukkeien Ginkgo in 1945

Ginkgo biloba, commonly known as ginkgo or gingko (both pronounced /ˈɡɪŋkoʊ/), also known as the ginkgo tree or the maidenhair tree, is the only living species in the division Ginkgophyta, all others being extinct. It is found in fossils dating back 270 million years. Native to China, the tree is widely cultivated and was introduced early to human history.

Extreme examples of the ginkgo's tenacity may be seen in Hiroshima, Japan, where six trees growing between 1–2 km from the 1945 atom bomb explosion were among the few living things in the area to survive the blast. Although almost all other plants (and animals) in the area were killed, the ginkgos, though charred, survived and were soon healthy again, among other hibakujumoku (trees that survived the blast).

The six trees are still alive: they are marked with signs at Housenbou (報専坊) temple (planted in 1850), Shukkei-en (planted about 1740), Jōsei-ji (planted 1900), at the former site of Senda Elementary School near Miyukibashi, at the Myōjōin temple, and an Edo period-cutting at Anraku-ji temple. Source: Wikipedia

To see the picture of surviving tress kindly visit the following web site: 
http://kwanten.home.xs4all.nl/hiroshima.htm