By the author of numerous adventure stories, most recently Greenhorn's Cruise (1964), the Ladder while it's pretty high up in the Swiss Alps, doesn't attain any great story-telling heights. 15 year old Simon and his 12 year old sister Mag, done out of a mountain climbing expedition, are permitted a compromise vacation with their bulldoggy Aunt Flora, an artist, who shows unfulfilled promise of being a Margaret Rutherford sort of personality. Aunt Flora has absolutely forbidden any climbing while the children are in her care, but Simon can't stand being right within view of a tempting peak. Mag contrives an involved plan which includes getting them all up the slope, straightening out a quarrel between two guides and hence reuniting a pair of starcrossed lovers. It still seems unlikely even as it comes off. There are some nice descriptions of the Alpine peaks.