Ms. Alghanem took note.

“I saw that we as Saudi women were powerless,” she said.

She invited other women to her home to discuss the issue, and they later decided to take action. They sent a letter to Salman — at the time the governor of Riyadh Province — telling him that they planned to drive.

They never heard back, they said, so on Nov. 6, 1990, they met near a supermarket in Riyadh, piled into 14 cars piloted by women with valid foreign licenses and drove around town.

They were social outliers, backed by no political party, and other Saudi women did not rush to join them. Many came from affluent families and had studied abroad. They included teachers, professors, a social worker, a photographer and a dentist.

Most were married with children; at least two were pregnant. One woman joined late, with her two daughters, one of whom was breast-feeding. Some had defied their male relatives to show up. Supportive husbands and brothers dropped off others at the meeting place.

Word spread, and the women were stopped by both the traffic police and the religious police, some of whom furiously banged on the cars.

“‘I want to dig a hole to bury you all!’” Fawziah al-Bakr, an education professor, recalled one man shouting at her. “They were thinking that we were going to destroy this country.”

They were taken to the police station and released around dawn, after they and their male relatives signed pledges that the women would not drive again.