During his campaign, candidate Trump faced massive protests in California over his hard stance on immigration. The protests often ended in arrests and destruction to property. President Trump may face similar resistance Tuesday in California.

President Trump will visit San Diego Tuesday to examine prototypes of the border wall. It is his first visit to the city since being elected. San Diego is the largest city on the U.S.-Mexico border to formally oppose his plans.

Numerous rallies are planned by groups both for-and-against Trump and his push to build a “big, beautiful wall” separating the two countries.

Protests are also being planned across the border in Tijuana, Mexico. Organizers on both sides were urging people to remain peaceful after recent scuffles at rallies in Southern California, including brawls at a Dec. 9 rally near where the prototypes stand.

California has become a focal point for clashes between state officials and federal authorities over the Trump administration’s immigration policies. The tension reached a fever pitch last month when Oakland Mayor Libby Schaaf tipped off illegal immigrant residents on imminent ICE raids, enabling several to escape.