Best ever - the national 400 in 2015, which started at Dingwall and went north.
In terms of regular calendar events, I used to enjoy the Cotswold Corker, the old Camarthanshire Snapper route was glorious but I didn't enjoy the revised route so much when I rode in 2019, and the Man of Kent 200 has always been a favourite. Tomsk's Hereward the Wake is a great ride too - I must enter that again next time.
I rode it only once, and finished a few minutes out of time, but Ian H's Kernow 600 was superb. I also liked Mark Rigby's BCM, but am less enamoured of the new route, particularly on the second day. The section from Newtown to Knighton was one of the highlights for me but I find the new route from there rather dull.
Finally, I think Audax Hackney's "Way to the Sea" 200 may become a favourite. When we are no longer required to limit numbers, I think that could become a biggie.