Limber Hill from Glaisdale

The start of this is definitely more than 20% and you need to be really very confident. When it is pouring with rain it is advisable to sit down and push because your back wheel will spin while your front wheel threatens to leave the floor. I failed the first part. In the rain. Next time, in the dry.

Although short and of a reasonably consistent gradient, it feels steeper than the chart suggests. Admittedly I arrived at the bottom with over 220km in my legs, but I and the dozens of other riders on that Coast To Coast bike unanimously agreed that it's a brute. My headset definitely hit 22％, and given that I was wrestling with the steep I didn't spend much time looking. The road kicks up sharply about 20m before a sharp right bend, and doesn't relent until after the slight left bend 200 to 300m later.