Sunk into a slope beside a stream in Portugal’s Caniçada Valley, the rear of this vacation retreat’s ground floor is deeply removed from the outdoors. Fortunately, architecture firm Carvalho Araújo found a way to direct natural light into the kitchen by pairing a skylight with a double-height funnel. The narrow band provides just a modicum of illumination, but it’s a potent reminder of the scenery on high.