There is no one fixed answer to what makes the best layering system. How many layers you need will vary form one person to the next. We are all a little different, and will need to adjust more, or less frequently than others around us. There are 3 main layers, that may consist of more than 3 items involved in a layering system. Your next to skin, or base layer, should be of a fabric that will wick moisture away from you (not cotton). This could be synthetic or wool based. The next layer would be a mid or warm layer. This may be a lightweight micro fleece or a down jacket, or both. How many mid layers you need will depend on the person and the time of year. This will also want to be something that will wick moisture away from you. Then you will need to consider your outer or shell layer. This may be a softshell (wind and water resistant) or hard shell (wind and water proof) depending on the weather conditions that are likely to be encountered.
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