Campaigners hold a banner reading "Build Bridges Not Walls" from Tower Bridge in London, to protest Donald Trump's inauguration as U.S. president, Friday, Jan. 20, 2017. (AP Photo/Matt Dunham)

LONDON — To send Donald Trump a message from across the Atlantic on the day of his inauguration, a group of about 30 volunteers picked one of the most dramatic settings in all of London: Tower Bridge.

The crew assembled before dawn on a bitterly cold London morning. During a misty sunrise that saw Tower Bridge’s Gothic-style towers bathed in orange light, the volunteers unfurled a banner that read: “Build Bridges Not Walls.” Some of the vehicles crisscrossing the bridge in heavy morning traffic responded to the demonstration with supportive toots.

The group behind the demonstration said that about 200 bridges around the world were draped in banners, in cities ranging from Auckland to Addis Ababa.

In London, many of the banners had diverse messages.

Anyone on a boat traveling down London’s River Thames on Friday morning — with their head cranked skyward — would have spotted a banner reading “Queer Solidarity Smashes Borders,” on Vauxhall Bridge, “Migrants Welcome Here” on Westminster Bridge, and “Unite Against Islamophobia” on Southwark Bridge.

Demonstrators hang a banner that reads "Queer Solidarity Smashes Borders" from Vauxhall Bridge, in London, Jan. 20, 2017. (Peter Nicholls/Reuters)

A banner reading "Migrants Welcome Here" is unfurled on Westminster Bridge on Jan. 20, 2017 in London. (Leon Neal/Getty)

“We’re trying to spread feelings of hope and positive messages here on this day that is going to be very hard for a lot of people,” said Claire Ryder, a 33-year-old history student with the campaign group “Bridges Not Walls.” She woke at 5 a.m. Friday to help kick off the demonstration on Tower Bridge. She is also one of the organizers of London’s Women’s March, which on Saturday is expected to draw tens of thousands onto the streets of London.

A native of Cleveland, Ryder moved to the U.K. in the fall. She said she was keen to do something to “help change the conversation and move forward.”

Demonstrators hold a banner that reads "Build Bridges Not Walls" on Ironbridge during a protest in Ironbridge, Britain. Jan 20, 2017. (Darren Staples/Reuters)

A man passes a banner reading "Build bridges not walls" that has been displayed on a bridge on North Parade on Jan. 20, 2017 in Bath, England. (Matt Cardy/Getty Images)

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