Participants of Singapore's first National Day Parade (NDP) in 1966 had less than 50 days to put together the event following the nation's split from Malaysia the year before.

While it was intensive, it was also memorable and significant, said the then-Regimental Sergeant Major Mr Shamsudin Shadan who features in the third episode of the National Heritage Board's documentary series - A Nation Remembers.

"My role was to help select and train Guards of Honour for our first parade and to make sure they could execute their drills perfectly to reflect Singapore's growing military strength," said the 80-year-old.

It was especially significant because there was an air of despair and despondency among new citizens following the announcement the year before that Singapore would be separating from Malaysia, said Mr Swee Boon Chai, 67, who marched in the parade as an officer cadet. The parade, which featured a total of 23,000 participants including 36 uniformed groups, served to foster a sense of social cohesion and optimism, said Mr Swee. The episode featuring these first-hand accounts alongside archival footage of the historical event will air on NHB's YouTube channel and website in August.