The event was set up in 2006 and initially took place on a small scale outside the Mochyn Du pub near the city centre.

[5] The main weekend event includes bars (selling amongst other things the specially brewed beer 'Cwrw Tafwyl') and street food outlets.

[5] The main festival is free to enter and in 2017 saw 38,000 visitors with a peak of over 8,000 in the grounds at any one time, compared to Cardiff Castle's maximum capacity of 5,000.

[7] Tafwyl returned to Cardiff Castle, but outgrew the site in 2023 and moved to Bute Park to use Coopers Field and the Sunken Lawn.

[8] Bands and performers appearing at the festival have included Bryn Fôn, Candelas, Elin Fflur, Geraint Jarman, Y Niwl, Meic Stevens, Sŵnami and Yws Gwynedd.