The half or full-length marathon Power Walking Challenge, the city's biggest mass-fundraiser for breast cancer causes, takes place from midnight on June 14 and will this year involve 12,000 participants.

Organisers hope their spirits will be buoyed during the gruelling march by a show of support from buildings along the 26-mile route.

Those already signed up include major city-centre stores, historic monuments and famous landmarks.

The Royal Yacht Britannia will blaze pink – the colour of the charity – across Leith, while the Balmoral Hotel's clocktower will light up the east end of Princes Street.

Scotland on Sunday's Holyrood headquarters will be a pink beacon as walkers trudge through the royal park.

Nina Barough, chief executive of the Walk the Walk charity, which has raised more than £4m in the last two Edinburgh MoonWalks, said: "This is a tremendous way of showing support for the thousands of walkers who turn out at midnight to take part.

"We can't play music because it's at night and we can't do activities because it is dark. But it is a great psychological boost to those taking part if they know people along the route are supporting them, even if they are tucked up in bed.

"If more people want to fly the flag for us in this way then we would love to hear from them. We can advise them how to do it."

Some of the buildings will be coating their floodlights with pink gel to change colour for the night. Others are buying pink fluorescent bulbs especially for the occasion, while some will project the charity's logo – in pink – on façades.

Yet others will have window displays of the charity's trademark pink bras.

Annette Lamb, spokeswoman for Harvey Nichols in St Andrew Square, said: "This is a fantastic cause and we will be delighted to support them in this way."

Ivan Artolli, general manager of the Balmoral, added: "On the evening of June 14 our dedicated clock technician will flick the switch, which will light all four faces of our iconic clocktower pink, using specially sourced fluorescent pink bulbs. The clocktower stands 120ft above the sixth floor of the hotel, which will ensure the pink glow can be seen from miles around."

The walkers will gather in the Meadows park from 8pm on June 14 before proceeding at midnight through Holyrood Park and past Calton Hill to Princes Street.

They will then swing back along Queen Street before heading north towards the Firth of Forth. At Silverknowes they will turn east towards Portobello and Joppa before heading back into the city centre.

Walk the Walk has raised more than £36m for cancer charities, and this year's funds will stay mostly in Scotland.

The bulk is expected to go towards a new Maggie's Centre at the Gartnavel Hospital in Glasgow, but the Breast Cancer Institute of Edinburgh's Western General Hospital will also benefit.

The centre will be built near the new oncology department in Glasgow, the Beatson.

It will complement the work of the other Maggie's Centre in Glasgow, the Gatehouse. Last year, the Gatehouse had 12,000 visits from cancer patients, and there has been a 60% increase in visitor numbers over the last two years.

At first blush

Scotland on Sunday is the media partner for the Edinburgh MoonWalk on Saturday, June 14, and our building will be pink for the night. If you want to join us in showing your support this way, contact Walk The Walk at www.walkthewalk.org. They will put you in touch with Northern Light, a company which can advise on how to turn your building pink.

Among the sites already committed to turning pink are: Royal Yacht Britannia; The Balmoral Hotel; Scotland on Sunday offices; Jenners window displays (with bras designed by students from the Edinburgh College of Art and a display by Narcissus Flowers); Nelson and National monuments, Calton Hill; logo projections on City Chambers and new council buildings on Market Street; John Lewis; Marks and Spencer; Harvey Nichols; National Galleries of Scotland; The Imagination Workshop, Marchmont; Gyle Shopping Centre; Ocean Terminal; Barbour's.