Deadly Lindt siege remembered - 10 years on

Sunday marks the 10-year anniversary of the beginning of the siege at the cafe on Martin Place, where Man Haron Monis took 18 people hostage.

At gunpoint, he forced hostages to call police and media organisations, falsely warning that he had placed bombs around the city, including in his backpack, and that it was an attack by Islamic State.

Cafe workers were made to press their hands to the windows while holding up a flag depicting the shahada, a Muslim declaration of faith.

The images of the terrified hostages standing at the windows for hours were widely broadcast.

Monis eventually fatally shot cafe manager Tori Johnson, while barrister Katrina Dawson was killed by stray police bullet fragments in the final moments of the siege.

After the tragedy, a sea of flowers washed over Martin Place, as family, friends and onlookers remembered the pair who were killed.

Ten years on, little remains at the site to remember the events of December 15, 2014.

The cafe is now a Dan Murphy's wine cellar, where a central tasting table is adorned with flowers in memory of those impacted by the tragedy.

A permanent exhibition is embedded into the concrete in Martin Place, with small flowers set into the pavement behind glass frames.

The floral display following the siege grew large as thousands paid tribute to the victims. (Dan Himbrechts/AAP PHOTOS)

On Monday, the NSW government erected a commemorative exhibition, displaying photos of the sea of flowers behind panels.

An 18-month-long inquest after the siege delivered a string of criticisms, including that NSW Police did not act quickly enough, the gunman should not have been allowed out on bail at the time of the siege, calls for help from the hostages went unanswered and victims' families were treated insensitively.

Coroner Michael Barnes also made a series of recommendations, many of which have been adopted into law and have changed the way Australia deals with domestic terrorist threats.