Metro ridership surged the day of the women’s march in downtown L.A.

Stations jammed with passengers and trains too full for riders to board were early signs that the women’s march downtown on Saturday had overwhelmed Los Angeles County’s rail system.

Just how many riders the system carried on the day of the rally became clear Tuesday, when officials said riders boarded Metropolitan Transportation Authority trains about 592,000 times Saturday— more than twice the typical weekend ridership.

Officials did not make data available for the county’s sprawling bus system, which carries nearly three-quarters of Metro’s riders in a given year. The figures also do not include Metrolink, the commuter rail system that serves six counties.

Like the attendance numbers for the women’s march itself, Metro’s ridership figure is an estimate, rather than a hard count. The estimate was based on hard data from tickets scanned Saturday, as well as counts “made in the field,” spokeswoman Kim Upton said.

The 592,000 figure is not an estimate of the number of transit riders, but of boardings — essentially, the number of times that people got on a train. Because many riders change trains or take a return trip, the number of boardings is typically higher than the total number of riders.

For example, a passenger who took a round-trip journey using the Expo and the Red lines would represent four boardings.

Saturday’s estimate represents paying and nonpaying riders, Upton said.

Metro sold more than 40,000 fare cards, suggesting that many riders use transit infrequently, if ever. Passengers reported long lines and delays at some ticketing machines.

At some rail stations, as crowds began to grow, operators told riders that they could board without paying and without fear of being penalized.

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