In Italy, Portugal and Spain, activists used water pistols and a “noisy stroll” of suitcases to draw attention to rising housing costs and the environmental toll of tourism.

Protesters used water guns against unsuspecting tourists in Barcelona and on the Spanish island of Mallorca on Sunday as demonstrators marched to demand a rethink of an economic model they believe is fueling a housing crunch and erasing the character of their hometowns.