MENTION Caernarfon Castle to anyone familiar with English history and they envision an English prince being invested with a Welsh title.

They would be partially right, but in truth it's so much more than just that. After Edward I defeated the Welsh, he actually had Caernarfon built as a walled castle town to protect his hold on the resistant north.

Then, in an effort to win them over, he created what today would be considered a masterful public relations manoeuvre. According to tradition, what happened is that the King and Queen Eleanor were on their second visit there in 1284 when Edward II was born in the castle's Eagle Tower.

It was the perfect opportunity to fulfil his promise to Welsh nobles to give them "a prince that was born in Wales and could speak never a word of English". And he was so proclaimed in 1301, as has every first-born male heir been ever since.

However, it was Prime Minister Lloyd George who brought the ceremony to Caernarfon with its present pomp and majesty. Since he represented this district as MP, focusing national attention on it suited his political purposes.

It was a very unusual and different sort of castle when I first visited back in 1968 on an assignment for The Chicago Tribune. To say that it's changed since would be an understatement. On my most recent return, it had become even more fascinating, thanks to the creation of interior museum displays that are quite spellbinding.

On that first trip, I spent a lot of time climbing up and down narrow circling staircases of turret towers, roaming through deserted ancient chambers and viewing a modest display involving history of the Welsh Fusiliers.

It's said the castle's designer, most probably James of St. George, sought to follow an architectural plan resembling the City of Constantinople. Captured by Crusaders in 1204, that Turkish wonder was still being much emulated when construction of this castle began in 1283 and progressed with unusual rapidity. There's no question stonework in its tallest turrets emphasises that appearance.

There were those who even called the estuary on which Caernarfon was built "The Welsh Bosporous". At one time water washed against its foundations, making access by water easy.

For those interested in history . . . whether it be military involvements, Welsh or British . . . this is a place to spend hours. I'd driven over from Bryn Bras Castle after a leisurely breakfast and not been in any rush to get started, because remembering that earlier trip thought it would be a quick walk-through.

When closing time came, I still needed a couple of more hours to do it all justice. The variety of material covered was intriguing. A few examples . . . just as the Navajo Indian tribe's language turned out to be a code enemies couldn't break in World War Two (as covered in the recent film Codetalkers), so was Welsh. The Fusiliers managed to confuse the enemy in Burma in 1944 and Bosnia in 1995.

You're being entertained while learning, since you tour to sounds of regimental music while climbing up those towers to different display levels. Happily, they now have hand rails to help manoeuvre the steepest, narrowest steps.

There's a display contrasting uniforms of 1689 and today, marvellous stories of heroism, all kinds of anecdotes and gems of history. Development of the musket, matchlock to flintlock and bayonet are also traced.One sergeant fought so bravely in 1745 when nearly half his fellow soldiers were casualties that he was commissioned a lieutenant. With that promotion his pay doubled from 11 pence daily to 22 pence. Eventually he became a captain and pay increased to 60 pence daily.

Can you imagine marching 58 miles in 24 hours? It happened and an infantryman in those days would be carrying a knapsack weighing around 45 pounds including such necessities as his sword, clothes and shoe brushes, six days' provisions, a blanket and so on.

THE Museum of Welsh History in another tower takes you back to Roman times. There's a bit of everything here, from weapons of every description including the Crimean War, to a Christmas box from HRH Princess Mary sent to troops in France for the 1914 holiday. We have some of these brass boxes in our personal military collection. They were given to every soldier until shortages made it impossible to continue.

Don't miss the gift shop. Some music tapes, especially those with harp music, were excellent. Knowing I'd probably soon wear them out overplaying them, it seemed a wise move to buy two of each selected.

Walk out the castle gate and discover an interesting craft store across the street. Also on that block was a happy personal find . . . a shop actually selling treacle candy. If given the opportunity, my family can devour it by the pound, but it's become increasingly hard to find.

A couple of years earlier we'd depleted the inventory at a sweet shop near Dorset's Corfe Castle, and the year before that the entire stock of an Oban confectionery en route to the Hebridean Isle of Mull.

Travellers will also want to explore the older section of town where the ancient encircling walls are still mainly intact. Two other attractions are on my list for my next, third visit. One is the Inigo Jones Slate Works six miles south of town, where visitors can learn all about how slate is quarried, cut, and engraved now and in the past.

The other is an Air Museum located eight miles southwest at an old RAF base. Exhibits and aircraft there sounded interesting, but time was running out. Explorer types find this is a good location for branching out on day tours and it's very pleasant to have your own personal castle to come home to after roaming off looking at others all day.

If there's time for only one more, what should it be? Remember you're in a country that has more than 400 castles and fortifications in varying stages of preservation . . . more than any other country in the world when one considers Wales' size.

Although I'd seen Harlech on that first trip and never forgotten its size or magnitude, a second look was irresistible. Driving back from dinner in that area quite late one night, it was impossible to resist detouring over to the coast for another glimpse.

There are some impressions so vivid and dramatic, they remain stored away in one's memory ready for instant recall. Approaching Harlech Castle along a narrow lane cut into the hillside, it came into view dramatically illuminated . . . not only by zillions of artificial wattage, but moonlight casting a bright beam over the water.

PERCHED on a rock at sea's edge, Harlech is another of those massive marvels built by Edward I as part of his "Iron Ring" defence insuring his continued control of Wales. This is another James of St. George creation, a name as renowned among British Isle castle enthusiasts as Vauban was in France.

Unfortunately, there are no scheduled moonlight tours, but just stopping on that hillside road and soaking up the view was spectacular. The freedom of having a rental car makes this sort of thing possible. Seize the moment, take to those winding country lanes even at the risk of getting hopelessly lost. It's certainly far more memorable than sitting around a hotel lobby talking to other tourists.

Like Bermuda's treasured St. George's, Harlech Castle is also a UNESCO World Heritage Site and very deservedly so. Yes, it was the inspiration for the famous Welsh song Men of Harlech.

Hopefully, you're not "castled-out" by now, because there are a minimum of three must-sees almost cheek-by-jowl from Caernarfon. Plas Newydd is a palatial country estate created by the Earl of Uxbridge and enjoyed by Queen Victoria as a young girl.

Now a National Trust property, it's full of imaginative treasures with no expense spared in creating its extravagant lifestyle. So much so, its last Marquess died in Monte Carlo hiding from creditors.

Penrhyn Castle is another example of a very grandoise lifestyle based on a Jamaican sugar plantation fortune and prosperous slate quarries. The first Baron Penrhyn started lavish spending to recreate a mediaeval atmosphere. Again, the National Trust has gone to impressive lengths to preserve this extraordinary complex.

To give you some idea of wealth that furnished its grandiose setting, the estate covered 72,000 acres in the late 1800s, with more than 600 farms in addition to the prosperous quarries. They yielded today's equivalent of more than $6 million profit annually. And every bit of that wealth shows in the idealised Norman castle country house.

I especially enjoyed exhibits in vintage buildings out near the parking area. They contain the Industrial Railway Museum with a unique variety of old locomotives.

Beaumaris is the third property, another of Edward I's castle towns. The setting is very dramatic with views over the Menai Strait and across to mountain vistas. It should come as no surprise it took 2,000 industrious workmen to fulfil the very busy castle-designer James of St. George's master plan. Intended to resemble Harlech, it was never entirely finished.

No wonder we came limping back to Bryn Bras Castle daily. Determined to see it all, we also circled the windswept Isle of Anglesey just offshore along the Irish Sea. We viewed wild cliffs of Holyhead Mountain, stomped around fields to view historic standing stones and abundant megalithic ancient burial chambers, plus two particularly intriguing chapels honouring Celtic saints.

Those hardy, often solitary saints who chose a life of hardship were certainly remarkable. A book was published before my last trip entitled The Book of Welsh Saints. During the fifth and sixth centuries, it's estimated there were as many as 900 who flourished during the so-called Dark Ages preserving their faith and knowledge. They emulated David, patron saint of Wales, who "emphasised the importance of the frugal and simple life . . . expected monks to harness themselves to the plough instead of using oxen, dress in skins, stick to a plain diet". His simple life was considered "a reaction against what he considered excesses of Anglo-Saxon bishops".

Anglesey has been an important site since Roman times, partly due to Parys Mountain's copper. By the 18th century, those mines were among the world's largest and battleships of the Royal Navy sailed the world with hulls sheathed in Anglesey copper. Long before that, around 3 AD, Romans had a naval base here. Why? To control pirates on the Irish Sea. (Now you can fast-ferry across to Ireland in an hour). It must have been a lively time.

Travel factfile:

Caernarfon Castle: adults $6.75, family $18. Open year round except Christmas holidays. Seasonal hours.

Plas Newydd near Llanfairpwll, Anglesey: adult admission around $7, children $3.50, family $16.60. House open April 1-November 1, noon to 5 p.m Saturday-Wednesday, closed Thursday and Friday.

Penrhyn Castle, two miles east of Bangor: adults $7.50, children $4, family $19. Late March to early November daily except Tuesdays, castle noon-5 p.m. July and August 11-5 p.m.

Web site www.cadw.wales.gov.uk has information properties mentioned above, and their Heritage Pass for reduced rates.

www.irishferries.com

www.anglesey.gov.uk

4 Next week: Grand finale wrap-up of Wales.