On Sunday in Bognor Regis, a series of displays and exhibitions are due to take place around the pier and Waterloo Square.
The day began with a parade along the promenade at BST followed by a drumhead service on West Green. More on this story. Street parties and parades are also taking place throughout the UK.
The official host city this year is Edinburgh. The council said an artillery re-enactment display with field guns and vintage vehicles will take place later on East Green.