A Sunday morning later this month will take on the colours and clatter of another age, as more than 200 men and women in full English Civil War dress gather in the heart of London.

The occasion is the annual march organised by the English Civil War Society to commemorate the death of King Charles I, executed on 30 January 1649. For more than half a century, the Society has marked the anniversary on the last Sunday of January with a solemn procession down The Mall, recalling what contemporaries described as the King’s “horrid murder”.

So, on Sunday 25th January, members of the reenactment society will converge on The Mall from all across the country, some arriving already dressed in buff coats and broad-brimmed hats, others changing into period clothing on arrival. There are pikes to be shouldered, muskets checked, and a few tentative practice swings as old drill is recalled, before the ranks are set and order restored.

The assembly takes place at the end of The Mall beside St James’s Palace, with the main march stepping off at around 11am and proceeding towards Horseguards Parade. There, a short service is held, and at about 12:30pm, a small detachment peels away from the  main body and passes beneath the arches to the Banqueting House.

There, a wreath will be laid on the spot where Charles I met his end.

Members of the King’s Army are careful with their language: they never speak of an “execution”, a term which implies lawful authority, but of a killing they maintain was illegal.

The loyal cheer for King Charles can still stop passers-by in their tracks, until it becomes clear that this is Charles, first of his name, not the current King Charles, third of his name.

After the parade on Horseguards, they head back to St James’s Palace for about 1pm.

This year’s parade takes place on Sunday 25th January and the whole thing is entirely free to watch, and quite amazing if you’ve never seen it.

An extra tip: Earlier in the morning, a second wreath will already have been laid at the base of the equestrian statue of Charles I at the top end of Whitehall, and that’s also worth a detour to see after the parade has finished.