According to Official Guinness Records,
The longest journey by a water jet pack is 36.45 km (22.64 miles) and was achieved by Pollyanna Woodward (UK) from Gozo Marina to Msida Yacht Marina in Malta, while recording The Gadget Show's 250th episode, on 08 November 2013.The journey set off from Gozo Marina, circumnavigated the island of Comino, before arriving at Msida Yacht Marina in Malta in four hours and forty five minutes.
For a complete list of 2013 records, please visit 2013 Guinness Records in Malta.