Look closely and you'll be able to spot how big this snail is. A STOMPer spotted this creature at Bukit Brown cemetry and couldn't resist sharing it with STOMP.
"I just saw this huge snail at Bukit Brown Cemetry today (April 12).
"I've never seen a snail that big in size before! It's close to palm size."
This is the giant African land snail (Achatina fulica), a native of Kenya and Tanzania that has been introduced to many tropical countries, including Singapore.
Here's another photo showing how large this snail can get:
(Photo by settka)
It's actually considered to be among the 100 worst invasive species. The page on this species over at the Global Invasive Species Database explains in detail the many ways in which it can wreak ecological havoc when introduced.
Giant African land snail, Singapore;
(Photo by travellingzenwolf)
Locally, this species is extremely common in most urban and suburban areas, and can often be seen crawling on the pavement especially at night or in the morning. First recorded in Singapore in the 1920s, it is not known how it arrived here, although it is plausible that trade between East Africa, India and Malaya helped expedite the process. This 1931 article from the Hong Kong Naturalist does give a little background information about how this African snail made its way to Asia.