1990 Oldsmobile Delta 88 won't start

1990 Oldsmobile Delta 88 mileage: 214,000. My car won't start, the battery is only two or three weeks old. The car gave no indication of a problem. I drove it all day-short trips-but after letting it sit for a few hours, when I tried to start her, it wouldn't turn over. All digital dash lights up, but no cranking of any kind. I replaced the starter, and still nothing. Please help.