"To bag a Munro" actually means to ascend one of the total 284 of the highest Scottish mountains. Those who manage to climb all the Munros are honourably called "completers". The Scotch Highlands fall into the very Munros which exceed 900 m in height and are less tall than the Corbetts and Grahams. These hills were named after their explorer Sir Hugh Munro who classified them. The safest conditions to climb the hills of Scotland are available between April and October.