One of the more unique IPOs of recent years is planned by a company called The London Tunnels PLC, with management hoping to turn a largely unknown and unused subterranean network of Second World War walkways and shelters into an international tourist attraction.
Originally constructed in the 1940s for civilian protection during the Blitz, the Kingsway Exchange Tunnels lie beneath one of the busiest parts of the capital.
The company behind the project, which has already raised £10 million in pre-IPO funding, is looking to bring in up to another £30 million in investment at £2 a share, giving the business a market valuation of £123 million.
Ultimately, the focus is on creating a multi-sensory experience that melds arts, nature and sciences, while preserving the area's historical significance related to WW2 and the Cold War.
However, initially, the cash will be put to use on preparatory work such as securing the permissions required to turn the dusty system into an international attraction capable of bringing in two million visitors a year.
Chief executive Angus Murray said: "This unique set of tunnels, owned by a British company, built by the British Government, for the defence of Britain, that can further enhance London's reputation as a leading tourist destination, should be listed in London."