This document discusses different types of curves in hill roads, including hairpin curves, salient curves, and re-entrant curves. It provides details on hairpin curves, which involve a 180 degree change in direction. Selection criteria for hairpin curves include a minimum straight length of 60m between curves and a minimum radius of 14m for the inner curve. The document also discusses drainage structures for hill roads, including side drains, catch water drains, and cross drainage works to divert surface water. Landslides are defined and causes such as increased water content, accumulation of snow, and vibrations are mentioned.