PORT DOVER, Ont. -- Sixteen-year-old Annaleise Carr completed her marathon swim across Lake Erie on Monday after returning to the water overnight to finish the exhausting final leg of her journey.

In the first leg of the 75-kilometre crossing in late July, the teen swam from Erie, Pa., to Long Point Ont., a distance approximately the length of 1,500 Olympic-sized swimming pools.

Stormy weather and rough conditions eventually forced the Walsh, Ont. native to end the swim 33-kilometres short of her goal, but she pushed through the second leg early on Labour Day, finishing in just over 12 hours around 11:45 a.m. in Port Dover, Ont.

Some 2,000 cheering supporters welcomed her ashore, a spokesman said.

"She's actually feeling fantastic, surprisingly, after swimming more than 30 kilometres," at an average speed of just under three kilometres per hour, Aaron Gautreau said.

"When she got out of the water I don't think I've ever seen a bigger smile on her face. The whole point of the swim is to send a message to people with cancer to never give up and that's exactly what she did today and she feels so great about that," Gautreau said.

"Finish what you started, don't give up on your dreams because of a complication or a road block, you just keep going and that's what this whole swim was about."

Carr is swimming to raise money for Camp Trillium, a camp for children with cancer, and has raised more than $193,000 at the time of her completion of the swim.

"The reception in the community was lots of tears, people are really touched by what this girl has done not only in her hometown (...) but for the entire nation," Gautreau said.

After completing the swim, Carr was presented with a commemorative scroll with a message from Prime Minister Stephen Harper and was also given a Canadian flag from Parliament Hill, he said.

Gautreau said the teen was "completely blown away" by the two gifts.

In August 2012, Carr -- who was then 14 -- became the youngest person at the time to swim across Lake Ontario, enduring a 27-hour swim from Niagara-on-the-Lake to Toronto.

That record has since been beaten, but Carr has raised more than $430,000 for the camp from the two swims, Gautreau said.

Carr gave a brief statement after completing the swim before being whisked off by her family in order to get some much needed rest.

"Right now it's just to rest, but do not be surprised if you hear her announce another swim in the future," Gautreau said.