Andrew Herschberger's girlfriend lives in Delta, almost 25 miles across the gentle hills of the Susquehanna Valley. But as a member of the Amish community, he may not drive a car, ride a motorcycle or even hop on a bicycle to go there.

He travels using an increasingly popular mode of Amish transportation, in-line skates.

''It's faster than a horse, and it's fun,'' said Mr. Herschberger, 20, who skates the 25 miles in two hours, almost twice as fast as an Amish buggy. ''You just feel free.''

Mr. Herschberger has abundant company on the roads of southeastern Pennsylvania. In the last few years, hundreds of Amish, most of them young, have taken up in-line skating to run errands, play hockey or just zigzag for pleasure.

Among the 150,000 or so Old Order Amish, who live in 230 settlements in 22 states and Canada, in-line skating is justified as an efficient, sensible means of locomotion, another example of how the modern can square with the traditional.