Hashes are running groups that run through rough terrains such as forest or wooded areas and even in the concrete jungle, guided by pre-marked trails (much like a treasure hunt). Groups are made up of locals and expatriates and are great to make new friends. For each run, there will be one or more people (called the hares) who will lay the trail with markings such as flour, paper or chalk. This is done before the start of the run. During the run, the runners will find these markings and follow the trail. To keep the group together, the hares usually set false trails so that the slow runners can keep up. After the run, the group gathers together for a post mortem of the run, generally drinking down loads of good beer.
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