It runs until Sunday 17 November and is said to be one of the UK's top festivals for outdoor enthusiasts. Organisers say it brings millions of pounds to the local economy every year. The programme includes a film festival, exhibitions, workshops and active sports events.
The 2018 festival attracted 16,000 visitors, with 18,000 tickets sold in total. In 2013 only 10,000 people attended. This year it's expected to bring up to 20,000 people to the town.
As a result, there are questions over whether it may have grown too big. This year most events sold out months ago, locals have been unable to purchase tickets, and visitors have been struggling to find accommodation.
Fiona Marley Paterson has been in Kendal to find out more.
Every year we see the festival grow in scale and ambition as more and more people discover the benefits of connecting with the outdoor world. Our programme is broader than ever before to represent and encourage a greater diversity in the people, places, and forms of adventure that we share. Kendal Mountain Festival's vision, however, remains unchanged and we seek to continue to inspire more people to explore, enjoy and represent mountains, wilderness, and their cultures.
Watch the full report on Lookaround at 6pm.