Read about history and pick out a good one!
https://en.wikipedia.org/wiki/June_21
2000 – Section 28 (of the Local Government Act 1988), outlawing the 'promotion' of homosexuality in the United Kingdom, is repealed in Scotland with a 99 to 17 vote.
2006 – Pluto's newly discovered moons are officially named Nix and Hydra.