One of the greatest challenges to people living on hillsides is that of hillside landscaping. The plantings will help keep the soil on your hillside intact. The main part of the house is concealed underground within the steep hillside, where large horizontal platform creates a nice living and entertaining area. In sharp contrast to its more traditional neighbors, this contemporary Swedish house plan features a flat roof and a minimalist black exterior framing its massive windows. Casa Barone is an ultra-modern hillside house designed by Sweden architects WRB.