The £275 jacket is described on the label's website as, "the ultimate throw-on summer jacket." Kate paired the jacket with black skinny jeans and chic layers, including a frilly white shirt peeking out from under a khaki jumper.
The 37-year-old also wore a trendy pair of lace-up ankle boots by Chloe, which Kate was last seen wearing in March during a visit to the Scouts' headquarters in London.
The Duchess of Cambridge on a walkabout in Keswick town centre
PA
Keeping a relaxed appearance, Kate fashioned her hair into a loose ponytail - a sensible option given this week's UK weather forecast.