Liverpool's Royal Liver Building is up for sale and is expected to attract buyers offering more than £40m for the landmark and its Liver Birds.
The Grade I listed property is being sold by Royal London Mutual Insurance Society. It is the first time it has been on the market since it was first opened in 1911.
The Liver Building began life as the home of the Royal Liver Assurance Group, but is now occupied by companies such as Princes Foods, ITV, HSBC, Mott MacDonald and Grant Thornton.
The Liver Birds crowning the landmark watch over Liverpool and, according to legend, if they fly away, the city itself would no longer exist.
The building is one of Liverpool's Three Graces on the city's UNESCO protected waterfront, alongside the Cunard Building and the Port of Liverpool Building.
CBRE are acting for Royal London to sell the 330,000 square feet of office space.
Colin Thomasson, who is leading the sale for CBRE, said: "We are delighted and extremely proud to be instructed to seek a purchaser for this truly iconic symbol of Liverpool.
"The Royal Liver Building is known worldwide and we expect the sale to attract strong interest from investors in the UK and around the globe.
"Our clients have been great custodians of this building for over 100 years, and this sale presents an extremely rare opportunity to acquire a unique part of Liverpool's heritage."