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Karen Zemlin

From Openwaterpedia
Karen Zemlin entering the first shipping lane during her successful English Channel crossing in 2019
Karen Zemlin sighting during an open water race.
Karen Zemlin during her MIMS swim in 2014.

Karen Zemlin is a 54-year-old American open water swimmer from Plymouth, Minnesota.

Open Water Swimming Highlights[edit]

  • On 18 June 2022, she finished 2nd at the Extreme North Dakota Watersports Endurance Test (END-WET) down-river 36-mile (57.9 km) marathon swim from Belmont Park, North Dakota into East Grand Forks, Minnesota along the Red River of the North in 8 hours 33 minutes at the age of 54.
  • She swam her first lake race at 13 years old. 40 years later, she has become a prolific marathon swimmer.
  • She grew up in Minnesota surrounded by lakes. Her father, Roger Bosveld, a marathon swimmer and long-time swim coach in Minnesota, introduced her to the joy of lake swimming. For them, swimming is about wind, waves and distant horizons.
  • She swam under Jim Brobin at Mounds View High School, who taught his swimmers that, "It’s what you do after you’re tired that counts." A saying Karen embodies in her swimming career.
  • During her collegiate years, Karen set 1000-yard freestyle school records at the University of River Falls and Hamline University that still stand today.
  • While swimming at Hamline with Marty Knight, she was named Hamline Woman’s Outstanding Junior Athlete, received the Pat Paterson Award, and later was inducted into the Hamline Athletic Hall of Fame.
  • After college, as a masters swimmer, swimming with coach Scott Tripps in Hopkins, she has set State Records in distance events in many master’s age groups.
  • She has consistently ranked in USMS Top Ten and appeared on FINA’s International Masters Swimming Top Ten.
  • She has been named USMS All–American six times for open water and pool events.
  • She is a member of the Minnesota Master’s Swimming Hall of Fame.
  • She achieved the Triple Crown of Open Water Swimming, swimming across the English Channel, the Catalina Channel, and swimming around Manhattan Island.
  • She has crossed Lake Mille Lacs twice.
  • She is the fastest woman of 50 years or older to swim across the 33.5 km English Channel.
  • On 9 April 2020 Karen Bosveld Zemlin was inducted into the Minnesota Swimming Hall of Fame, becoming the first member of the Hall of Fame to represent open water marathon swimming.
  • She holds the women's course record for the Point to La Pointe Swim in Lake Superior.
  • She is a member of the Half Century Club for the English Channel and Catalina Channel Half Century Club.
  • On 28 July 2012, she completed the 16.1 km Minnetonka Challenge in Minnesota in 3 hours 49 minutes 6 seconds at the age of 44. 2nd place overall, 1st place female
  • On 13 July 2013, she completed the 43.5 km END-WET from Grand Forks in North Dakota to Oslo, Minnesota in 6 hours 58 minutes at the age of 45. 1st place overall *Course record for the 43.5k course
  • On 14 June 2014, she completed the 45.9 km Manhattan Island Marathon Swim in New York in 7 hours 23 minutes 44 seconds at the age of 46. 3rd place overall, 2nd place female
  • In August 2014 she completed the 32.2 km Apostle Island Relay Swim around Madeline Island Lake Superior in 8 hours 49 minutes at the age of 46 as a solo swim. 1st place overall
  • In August of 2015 she completed the 14 km Henley Marathon Swim Bridge to Bridge in the Thames in 3 hours 20 minutes 39 seconds, age 47, 1st place overall all ages
  • In September 2017 she completed the 16.1 km 16th Annual La Jolla Cove 10 Mile Relay in 3 hours 30 minutes and 12 seconds at age 49, solo swim, 1st place female, 2nd place over all
  • On 21 April 2018, she completed the 37 km Tampa Bay Marathon Swim in Florida 9 hours 55 minutes, age 50. 1st place overall
  • On 19 September 2018, she completed a 32.3 km crossing of the Catalina Channel from Santa Catalina Island to the Southern California mainland in 9 hours 44 minutes 31 seconds, age 50. Fastest female swim in 2018
  • In June 2019 she completed the 32.1 km Lake Mille Lacs from Isle, Minnesota to Garrison, Minnesota in 9 hours 55 minutes 20 seconds, age 51 *course record, first documented swim of Lake Mille Lacs
  • On 24 August 2019, she completed a 33.5 km crossing of the English Channel from England to France in 10 hours 17 minutes, age 51, the fastest ever recorded by a woman over the age of 50 and the third fastest by anybody in that age bracket male or female, 3rd fastest time out of 151 in 2019
  • On 31 October 2021 Karen completed the Swim Around Charleston a 20.12k (12.5 mi) swim in Charleston Bay in 4 hours 22 minutes and 59 seconds. She was fourth place overall and second place female swimmer at age 53.

Some fun facts about Karen:[edit]

Notable Quotes[edit]

  • Catalina Swim Association observer: "She was all business. Got in, swam like a maniac, got out. And, just like that, all done!"
  • CS&PF Tweet: "Excellent swim and apparently a seal was waiting as you climbed on the rocks!"
  • Karen Zemlin on her second English Channel attempt: "I invited the cooperation of the English Channel."
  • On her Mille Lacs swim: "With so many fabulous lakes in Minnesota I think it would be great to get more recognized as marathon swimming opportunities."
  • Ron Collins on Karen's Tampa Bay Swim: “Swimming on a calm day, going the length of Tampa Bay in less than 10 hours is an amazing feat. Karen was able to battle choppy 1-2 foot waves and a 15-knot wind right from the start to win the event."

2018 Tampa Bay Marathon Swim[edit]


The Extreme North Dakota Watersports Endurance Test or END-WET, is a 27-mile (43.4 km) mixed-sports event where solo and relay swimmers pit themselves against other endurance athletes down the Red River between Grand Forks, North Dakota and Oslo, Minnesota in the United States. It is one of the longest marathon swims in the world and directed by Andy Magness.

External links[edit]