Kei Lily - Cyrtanthus sanguineus

We've had a shallow pot of these bulbs in the garden for twenty years or more - completely neglected, and yet they seem to flourish:

The flowers are spectacular.

Didn't know what they were until our neighbour, Eleanor, told us she had one and had been told it was a Kei Lily. I was a bit sceptial, but sure as anything Google confirmed it...