Today marks the 65th birthday of a butterfly legend from a country that has produced a fine shoal of women swimmers - but just the one Ada Kok. There'll never be another quite like her.

Described as “the gentle giant” of swimming, Kok, the 1968 Olympic 200m butterfly champion, broke more butterfly world records - 9 in all plus a quarter of a 4x100m medley mark - than any other woman ever has to date. She also attracted the following appraisal from Buck Dawson, the first Executive Director of the International Swimming Hall of Fame“… she looks like a football fullback and swims like a fastback”. 

Born in Amsterdam precisely two years after D-Day, Kok made her Olympic debut with two silver medals at the 1964 Olympic Games in Tokyo, four years before the introduction of the 200m butterfly. Over 100m, she arrived as world record holder (1:05.1) but Sharon Stouder, an American who won three gold medals (100m butterfly, 4x100 freestyle and medley relay) and a silver (100m freestyle behind Aussie sprint queen Dawn Fraser) stole her world mark in 1:04.7, to Kok’s second-place 1:05.6. 

In relays, Kok often turned depressing deficits into medal-winning opportunities for the Orange squad, and in 1964, her efforts brought Holland from outside the reach of the podium to a place from which Erica Terpstra, fourth in Fraser’s last 100m freestyle triumph, could race to the silver medal in a European record of 4:37.0 behind America’s 4:33.9 world record. 

Her lowest and highest moments unfolded at the 1968 Olympic Games in Mexico. On October 17, 1968, she and her medley relay teammates finished seventh behind four other European quartets a year after winning the European title. Then, on October 21, Kok entered the final of the 100m butterfly as world record holder on 1:04.5 (a time she clocked in 1965 and one that would survive until 1970) but emerged with the same time, 1:06.2, as bronze medal winner Susan Shields (USA) behind champion Lynette Clements, Australia’s first female butterfly champion whose daughter Jacqueline McKenzie raced at the 1992 Olympic Games, and Ellie Daniel (USA). Kok was distraught but it was not in her nature to be defeated. 

Three days later, having clocked the best heats time over 200m, she confirmed her standing as one of the all-time greats of butterfly swimming: third at the turn 1.4sec behind East German Helga Lindner, Kok fought back stroke by stroke and drew level with just three strokes to go and stole the crown by 0.1 over Lindner (a cousin of Renate Vogel, silver medal winner for the GDR in the 4x100m medley four years later and first world champion over 100 and 200m breaststroke in 1973), in 2:24.7, with Daniel third in 2:25.9. 

So delighted was Kok that at a reception at the Dutch Embassy in Mexico she accepted a bet to go and bounce on the ambassador’s bed - and got caught in the act. The ambassador simply smiled. 

She would later reveal the torment she felt after the 100m final and how she felt about events thereafter:

"Normally after a race there were always people around me. This time nobody. Nobody. I suddenly felt so abandoned and alone. Then under the shower I lost control and cried my eyes out. For the 200 meter final, I was so stiff and rigid that I couldn't even see myself getting my tracksuit bottoms off. My fingers couldn't get the zipper undone. An official had to help me with it. I don't remember anything now of the first hundred metres. It's a black hole. Well anyway, after 150 meters I was in the lead. Twenty meters from the finish, I saw someone [Lindner] catching up with me. I thought, 'Jesus, no, she is not getting past me.' Fortunately, I was able to keep in front."

In her memoirs, penned by Henk Lichtenveldt, she notes: "Approaching the podium of honor I felt like I was walking on clouds. I had to contain myself because I wanted to rush over the stands skipping like a foal. This was the crowning moment in a great swimming career."

If her place in the world swimming pantheon is assured, the plinth she built in European waters is among the tallest in the continental hall of honour. Over 100m between 1962 and 1972 Kok was the only woman to hold the European record (5 times); over 200m between 1965 and 1970 only Kok held the standard (4 times). During the Sixties, she also claimed all European butterfly titles available, the 200m only introduced to the continental championships in 1970. She swam at a time when Forbes Carlile (91 this week ... many happy returns to the pioneer coach) was at the helm of the Dutch squad.

In 1962 and again in 1966, Kok won the European 100m butterfly crown and helped Holland to gold in the 4x100m medley relays. At the 1966 championships in Utrecht, she also gave a hint of the talent the world rarely saw when she finished second in the 400m freestyle half a second behind Claude Mandonnaud, of France. That same year, Kok helped to open the International Hall of Swimming Fame in Florida, and was inducted as an honoree 10 years later. Over six years she held 13 European metres records (nine on butterfly and four in the Dutch medley relay).

There to see Kok's first world records in the 200m butterfly at De Vliet during a Canada Vs Netherlands duel was Nick Thierry, founder of SwimNews and Canada team coach in the 60s, and there to see her first 100m world record, at Soestuiden, were Forbes and Ursula Carlile, the Australian pioneers.

"And it was freezing cold, with drizzle and probably around 10-12C temp," recalls Thierry of the duel when the first race of the meet produced a world record. "We competed without warming up in the pool. Starts were by a whistle rather than what we were used too a starting pistol - and in the first event the Dutch went while the Canadians waited for a pistol! That's were Ada broke the world record with a whistle start."

In their birthday message to Kok today, Forbes and Ursula Carlile recall the same moment, writing to the Dutch champion: "Ursula and I remember well the first record when you must have been about 15. We recall the day when in the freezing  cold water of the open “Nature Bath” somewhere in the countryside, [when] you first made the WR for 100m butterfly!

Remember we had you running up and down the hill next to the pool to help your muscles warm? So many wonderful memories of the time we spent in Holland with the beautiful Dutch people, amongst whom Ada Kok, during and after those 50 years past stands out in my 91 exciting years (birthday, at a meet, on June 3rd, last Sunday)."

The Canada team report of the 1965 tour and 200m 'fly record recalls:  "Our good weather ran out in the Netherlands where the canals were bulging with a record rainfall … the final swim meet of the tour was held Saturday Aug. 21st in a  50 metre unheated outdoor pool with rain and a very cold air temperature. Ada Kok broke the World Record for the women's 200 metre butterfly with a time of 2:25.88 in the very first event!" Kok was way ahead, Elaine Tanner nearest to her in a  Canadian record of 2:37.2.

A quirk of swimming history dictates that Kok, officially speaking, remains a double world record holder to this day: during the 1968 Olympic Games, FINA decided that yards swims would no longer count for world records as of the end of that year. The book of yards world records for women's butterfly closed on December 31, 1968 with Kok the last holder in both the 100 and 200y, her efforts of 1:05.1 and 2:21.0 surpassed many times over in college swimming since but the Dutchwoman will forever remain world record holder on butterfly by an imperial measure that has survived only in the United States as far as elite competitive swimming is concerned.

Kok's impressive stature and strength on butterfly made her a role model for those building the East German medals machine to come. GDR officials asked permission of their Dutch counterparts at a European championship in the 60s to borrow Kok and take her to a gym, put her through some physical exercises, monitor her response and measure her might. The information was part of research designed to create the GDR's talent ID programme, one that would surely have earned wide acclaim had it not been for the fact that temptation strayed to Oral Turinabol to take nature and make it a bulked-up winning cert. It would not be the first time that Kok came into contact with the GDR.

Swimming did not lose Ada Kok when she retired from racing: she spent four decades as the crucial link between swimmers and their kit as the face of Speedo on the pool deck, her popularity in the place she called home undiminished down the years.

While working for Speedo, one of her briefs was to get the GDR wearing the famous brand. That meant many a contortion to get a visa, many a trip through Checkpoint Charlie to see a certain Herr Schmidt. He had an office with just a table and a couple of chairs in it. Sparse and spartan in communist cut. He was in charge of contracts for the GDR team. Many a sample, many a freebie ended up in the man's hands and when Kok showed up at events, she would see the GDR girls wearing her Speedos in the warm-up, before switching to home made kit and Porylastic numbers for racing. Kok was often left waiting for many hours on end at the checkpoint for no other reason than to make her feel uncomfortable.

The memory of those days lived on in her. Years later, after the Berlin Wall fell, she attended a reception in Germany and who should be one of the quaffers in the crowd? Herr Schmidt. How nice to see you, he said, adding that if she had only slipped something under the table during those meetings in the sparse office that resembled an interrogation room, the GDR might have worn Speedos after all. Lucky escape for Speedo - not so for Her Schmidt, who received a public dressing down from the Dutch champion, the room stilled by her words, the face of the man as red as the Dornfelder being poured.

During her years with Speedo, Kok played a blinder with the media, keeping journalists in touch with trends from the deck and giving a human face to the stories of swimmers whose personalities were often masked by a cap and goggles in an element that softens the perception of just how tough a sport swimming is.

Many hours of laughter are in the mix of memories held by those who have spent time with Ada Kok. Among my favourite tales from the book of Ada's Adventures is this one: out shopping one day, she sold her car to a passing gypsy, popped into a local optician with the cash and returned home sporting new glasses. Her long-suffering husband Math asked: “Where’s the car?” Lifting her glasses up and down off the bridge of her nose, Kok replied: “You’re looking at it.” 

There'll be a swish party this weekend - hold on to your hats. 

The swim legend retired from the grind a couple of years back but remains active in Olympic circles. Much missed on the aquatic trail, she remains, by her record and popular consensus, one of the all-time greats of a stroke that became official when she was just five years old.

Happy Birthday Ada Kok.