Shetland wool lightweight sweater used on the 1933 Everest expedition

Shetland wool lightweight sweater, one of two, from equipment used on the 1933 Everest expedition by Sir Jack Longland

The 1933 Everest expedition team knew that wearing multiple thin layers was warmer than one thick layer. For thermal insulation under their windproof suits, they had lightweight Shetland wool jumpers which could be layered. One of the climbers, Frank Smythe, wrote that during his summit attempt he wore six jumpers like this. The Shetland Islands are particularly well known for their sheep which produce high quality wool, and for the excellent knitted products that are made there.