In San Diego , which is near Tijuana , Mexico , and is the nation 's busiest border crossing , about 20,000 demonstrators gathered at Balboa Park and marched downtown to a rally .
Mexico /location/location/contains Tijuana
IN NNP NNP , WDT VBZ IN NNP , NNP , CC VBZ DT NN POS JJS NN VBG , IN CD NNS VBN IN NNP NNP CC VBD NN TO DT NN .
Mexico
LOCATION
Tijuana
LOCATION
/location/location/contains