11.   Other studies project robust demand for metro optical systems connecting businesses to the abundant long-haul fiber and to remote data-storage centers.

12.   Plus, like the rest of the city, use of the Metro system is readily available.

13.   Riders of the Metro system will find similar surprises.

14.   The surprisingly small nerve center of the Metro system flickers with video monitors and computer screens.

15.   Their stations are also deeper than those used by the Paris metro system.

16.   Buses provided minimum services, as mandated by the government, and the Madrid metro system ran with about half its normal number of trains.

17.   Buses provided minimal service, as mandated by the government, and the Madrid metro system ran with about half its normal number of trains.

18.   Even using the Metro system can be tricky.

19.   Signs warning that it is illegal to eat or drink on the cars and in the stations are posted in the Metro system.

20.   Suburban trains ran sporadically while the Paris metro system was brought virtually to a standstill.