LONDON -- It was the best of times, it was the worst of times. But, 2016 is finally drawing to a close.

As we reflect on the events that have defined the year, YouTube has revealed which trending videos dominated 2016 -- be they viral challenges, adverts or music videos.

And -- needless to say -- there are a few surprising contenders.

Most viewed YouTube videos in the UK

Unsurprisingly, Adele's hilarious stint on Carpool Karaoke topped the list of the UK's most viewed YouTube videos, followed by a diverse array of videos that have tickled the UK's fancy this year.

1. Adele Carpool Karaoke

2. John Lewis Christmas advert

3. Boogie Storm makes Simon's dream come true

4. YouTubers' crossbar challenge

5. Singing impressions with Conor Maynard

Most viewed music videos of 2016, globally

Work was a strong theme in music in 2016, with both Fifth Harmony's "Work from home" and Rihanna's "Work" in topping the list of most viewed music videos of the year.

And, by the looks of the list of top five videos, it's been a good year for Rihanna...

1. Fifth Harmony -- 'Work from Home' ft. Ty Dolla $ign

2. Calvin Harris -- 'This is What You Came For' ft. Rihanna

3. Hasta el Amanecer -- 'Nicky Jam'

4. The Chainsmokers -- 'Closer' ft. Halsey

5. Rihanna -- 'Work' ft. Drake