Enduro MTB is a pretty new discipline, as far as cycling goes. It’s kind of a cross between Downhill, cross country and Marathon mountain biking – a stage race format, with multiple events over a weekend, and competitors also riding the (mostly uphill) transfers between the (mostly downhill) stages. If you want to know more about it, there are the wikipedia article, and introductions from Pinkbike and BikeRadar, and this video from GCN MTB.
The Enduro World Series is the biggest competition, a season-long series that takes place in some truly gorgeous locations. It’s only been running since 2013, and it’s very definitely outside the umbrella of the UCI, organised by the Enduro Mountain Bike Association (EMBA), which itself started in 2012, and from the start, it’s been very inclusive, especially of women, but also of fans. It has excellent media, with lots of rider involvement, in the previews of each race, highlights, and lots of things in between, and it makes these available to pretty much everyone. Check out the video page and photo galleries on their website, and drool over that beautifully-MTB combination of fantastic people doing extraordinary things on amazing bikes, in the most incredible landscapes.