After the systematic error when we went to the Secret Cave, this time we remembered to adjust the altimeter in the car park in Buttermere before we set off. The car park was close to the 110m contour. Then we climbed Whiteless Pike, which is 660m tall. The altimeter said 650m on the top, which is not bad. Looking at the map now, I suspect we misread the start height and were out by about 10m before we set off. Bad calibration leads to systematic error later on.
