Greenpeace activists begin to hang a banner on one of the two Gate to Europe towers in Plaza de Castilla, Madrid, Spain, Tuesday, May 17, 2016. Greenpeace activists have scaled an emblematic Madrid office building to hang a banner protesting the free-trade deal being negotiated between the U.S. and the European Union. Greenpeace said the Trans-Atlantic Trade and Investment Partnership, or TTIP, threatens to undo many health, social and environmental protection measures. (AP Photo/Paul White)