“The only thing that ever really frightened me during the war was the U-boat peril”, wrote Churchill of the threat posed by German submarines.

Today there is only one surviving U-boat in Britain, the U534; sunk in a depth-charge attack in May 1945, the submarine was raised in 1993 and is now displayed on Merseyside as a memorial to the 70,000 men who died in the Battle of the Atlantic.

The Battle of the Atlantic was crucial to Britain’s survival during World War II: had the steady supply of armaments, food and men from North America been severed, then the war’s outcome would have been very different. The campaign was masterminded from Liverpool, at Western Approaches Command, where the basement bunker has been carefully restored to provide a resonant reminder of the darkest days of WWII.

The north-west of England is dotted with installations that recall later conflicts, notably the Cold War. Hack Green nuclear bunker, hidden amongst the rolling farmlands of Cheshire, has played multifarious roles in the defence of the British Isles. Once a bombing decoy site, Hack Green later served as part of the RAF’s “home chain” radar system and then as a Cold War radar station. In 1976 the Home Office converted the original bunker into a vast underground shelter to accommodate a select band of civil servants and military personnel in the event of nuclear attack.

Drakelow forms a compelling contrast to Hack Green: built on the site of a cluster of troglodyte cave dwellings, this remarkable network of tunnels operated as a “shadow” factory for Birmingham’s Rover engineering plant before being transformed into a regional seat of government and finally an RGHQ.

We stay at the four-star Macdonald Hill Valley Hotel just outside the Shropshire village of Whitchurch. The hotel offers ample car parking and is situated less than two miles from Whitchurch railway station.