[0xADD1E]

For the UK at least, there’s https://www.gov.uk/bank-holidays.json

[echoangle]

What does "bunting" mean in the date entries?

[BTinfinity]

Bunting just means decorations, the value is true when the government recommends decorating for the holiday. It's reserved for celebrations, so events like the queens funeral have it set to false.

[moritonal]

Personally this (along with things like address lookup) are things that I consider a government should always provide. Consistent data.