A 21-year-old German tourist who wanted to visit his girlfriend in the Australian metropolis Sydney landed 13,000 kilometres away near Sidney, Montana, after mistyping his destination on a flight booking Web site.

Dressed for the Australian summer in t-shirt and shorts, Tobi Gutt left Germany for a four-week holiday on December 30.

Instead of arriving "down under," Gutt found himself on a different continent and bound for the chilly state of Montana.

"I did wonder but I didn't want to say anything," Gutt told the Bild newspaper. "I thought to myself, you can fly to Australia via the United States."

Gutt's airline ticket routed him via the US city of Portland, Oregon, to Billings, Montana. Only as he was about to board a commuter flight to Sidney -- an oil town of about 5,000 people -- did he realize his mistake.

The hapless tourist, who had only a thin jacket to keep out the winter cold, spent three days in Billings airport before he was able to buy a new ticket to Australia with 600 euros in cash that his parents and friends sent over from Germany.

"I didn't notice the mistake as my son is usually good with computers," his mother, Sabine, told Reuters.