Pennsylvania not only has a lot of beautiful old covered bridges, it also has beautiful stone houses and barns, at least in Lancaster County and along the route of the Pennsylvania Turnpike (I-76 and I-70). This lovely house is on the north edge of Christiana, in the eastern part of Lancaster County. Our quest was the Mercer covered bridge (photo posted earlier), but stumbling upon this old house was a nice bonus. The colors in the stones and the variety of their sizes are particularly…