Best sun protectionA cap with a removable neck cape, for the exposed approach
Outdoor Research Sun Runner Cap
UPF 50+, detachable sun cape
The cape covers the ears and neck that burn first and that no sunscreen ever gets reapplied to; you will look faintly ridiculous, and everyone who has burnt their ears at 4,000 m stops caring.
Covers the two places people actually burn
Cape detaches when you stop needing it
Packs flat
Looks odd
Cape flaps in wind
Not warm in the slightest
Not for you if: Winter trekking, where the problem is cold rather than sun.
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