For almost 1,000 years it’s guarded the gateway to England and now walking in the footsteps of William The Conqueror, Henry II and Winston Churchill at Dover Castle has become even more exciting.

Interactive exhibits, new, authentic decorations and even live action shows, are helping to bring the past vividly to life.

Few buildings can claim to have been so intimately involved in the story of our country since William The Conqueror first built fortifications on the site soon after the Battle of Hastings in 1066.

And ever since, the castle has guarded our shores against the threat of invasion.

It was Henry II who built the impressive keep in the 12th Century that looms over the port. It served both as a palace to welcome foreign visitors in style, and also as a formidible fortress, in order to dissuade invaders from making the short hop across the Channel if they had anything other than good intentions.

And it was in our country’s darkest hour in 1940 that Dover Castle again showed it had a role to play in modern warfare.

A honeycomb of tunnels, which had originally been built in the 18th Century to garrison soldiers, was updated during World War II and acted as the operations room from which the evacuation of soldiers from Dunkirk was organised, known then as Operation Dynamo.

Even after the threat of Nazi domination had passed, the tunnels were planned to be used as a regional seat of Government in the event of a nuclear war.

It’s a proud record of service that is unsurpassed and within the castle’s walls there are even the remnants of a Roman lighthouse, which show the area’s importance even 2,000 years ago.

But it’s being able to visualise and imagine life as it was all those centuries ago that makes a day trip to this magnificent castle a treat for all ages. Even if you are not a history buff, or are too young to understand the concept of kings, pomp and circumstance, this is an exciting place.

On the walk up to the hill-top castle, my 12-year-old twin nephews Matthew and Joshua immediately did their best to ‘breech’ the castle confines as they realised the climbing potential of the steep, grassy hills, along with other eager, energy-filled youngsters.

As we entered through Colton’s Gate, we made our way to the inner bailey and the Great Tower, which dominates the scene. And it’s here where English Heritage has spent over £2million creating a stunning walk-through exhibition retelling the story of Henry II and his family. The beautiful interactive exhibit explains, however, that he had almost as much trouble with his own warring family – wife Eleanor of Aquitaine and sons Richard ‘The Lionheart’ and the notorious John - as he did from the marauding French.

Treading in those ancient footsteps down stone corridors, even spotting the odd ghostly figure here and there, the castle's daily routine came to life including the vast kitchen, where the court’s food was prepared and ale and wine made too, the armoury, staterooms and even original toilets. But most impressive were the newly-installed, and surprisingly brightly-coloured wall hangings and adornments in the main castle rooms. They have been recreated just as they would have been in the 12th Century to impress VIP guests.

It was a great surprise to ‘meet’ Henry and Eleanor in the flesh as they argued and discussed weighty matters of state and personal problems (well, even Royalty have worries too) in their grand bedchamber. A small, spellbound crowd of visitors listened as the actors verbally sparred with mention of Eleanor’s beloved son Richard and his fiancé (who was staying in the castle) for whom Henry seemed to be developing an unseemly attraction. Fascinating stuff.

Climbing to the top of the Great Tower, visitors are rewarded with an amazing 360 degree view, inland and across the modern Dover port. It is easy to realise how this remained one of England’s most important defences, as part of the five Cinque port fortifications along the south-east coast.

And from the highest point of the castle, to the lowest – tunnels have also proved important for troubled times in ancient and more modern history. Near the Tower there are medieval tunnels mined after the Great Siege of 1216 to explore, but more famous and extensive, a short walk down the hill brings you to an underground network, first built and used during the Napoleonic Wars of the 18th Century and in the 20th Century during the World War II.

Booking a timed tour brings you down to where troops were barracked in tunnels cut through the soft chalk of the Dover ‘white’ cliffs. Following a short, informative film to set the scene, we were led to see the operation rooms, dormitories and underground hospital. In a heart-stopping moment, the sights and sounds of that terrible time were brought loudly to life including a complete blackout during an air raid.

One nephew later pronounced this his favourite part of the trip. We emerged after about half an hour into the light, squinting, but excited and humbled by what we’d seen and learned. Altogether a tiring (lots of walking), but totally fascinating day out.

Top tips

Wear comfortable walking shoes – lots of steps and walkways to navigate.

Watch out for special events throughout the year, some of which are listed below.

Take a ride on the land-train around the castle – it’s fun and saves energy!

The Secret Wartime Tunnels are soon to benefit from an upgrade from September 2010 to summer 2011, so check for closures online or by phoning the booking line. The rest of the castle site remains open year-round.

There is a choice of cafes and restaurants serving hot and cold food and afternoon teas, or there’s plenty of space to enjoy a picnic.

Special events

Secrets and Spies (August Bank Holiday Weekend, Saturday August 28 – Monday, August 30) Children can test their super-sleuth skills for a fun ‘Time Travellers Go…’ activity (£1). Try out wigs and moustaches and find out how real double agents and spies his secret information.

Medieval merrymaking (every weekend in September) Enjoy some entertainment 12th Century-style when the kitchens and banqueting hall of the Great Tower will be alive with activity as costumed actors bring to life the sights and sounds of the Royal Household at harvest time. Sup wine, food and beer of the times, learn a medieval dance, and take in some tips from the castle huntsman.

The Haunted Castle (October 25-31) Phantoms come back to life in a week of frightening fun in the ancient castle’s corridors. Daily prizes for scariest children’s fancy dress.

Details: Adults, £13.90, children, £7 or £34.80 for family of four. Open seven days a week throughout September 10am- (last entry) 5pm. Find out more by calling 01304 211067 or book online at www.english-heritage.org.uk/dovercastle

Also visit…Walmer Castle

Just a few miles along the coast, another of the Cinque port fortifications, this is an altogether different experience, but equally fascinating. Small, but perfectly formed, this is a castle that is more like a home. It has played host to the Duke of Wellington and the Queen Mother in their duties as Lord Warden of the Cinque Ports. The rooms are elegantly furnished and set out just as it would be during a Royal visit. You can even see Wellington’s boots that started a fashion for us lesser mortals.

During her 24 years as warden, the Queen Mother would host a private dinner followed by a cocktail party on the Bastion overlooking the sea. We were lucky enough to do the same, enjoying sumptuous local fayre including seafood from Whitstable market, Beef Wellington (of course), sausages from Walmer’s butcher known as John’s and local cheeses. As the Queen Mother was reputed to have a sweet tooth, we couldn’t refuse meringues with soft fruits (raspberries were her favourite) from the garden and her absolute top choice, Chocolate Ganache Cake. This was washed down with wine from Biddenden Vineyard in Kent and tea and coffee from the Kent and Sussex Tea Company. The gorgeous gardens, given to the Queen Mother on her 95th birthday, are especially worth a visit. You can play croquet, take a woodland walk or wander around the sumptuous kitchen garden. If after all that, you can’t bear to leave, rent one of the holiday cottages on site.

Details: Day tickets - Adult, £7; children, £3.50; family, £17.50. Open throughout August and September, 10am – 6pm. Telephone: 01304 364288, www.english-heritage.org.uk/walmercastle