Climate activist Greta Thunberg banned from Venice after Grand Canal dyed green

[Emrys]

2. Chicago would like a word ...

I heard they banned her from Venice for all of four hours, so they must have been REALLY annoyed.

It's been done before anyway, in 1968, in fact:

Nicolás García Uriburu, Coloration of the Grand Canal, Venice

A 3-kilometer-long painting

This may look like a photo of St. Patrick’s Day in Venice, but it was actually a June morning in 1968 when the Argentine painter Nicolás García Uriburu climbed aboard a gondola on Venice’s Grand Canal to embark on his largest and most ambitious painting to date. He enlisted the help of Memo, a gondolier, to transport him up and down the city’s main canal as he dyed the water a vibrant chartreuse green with 30 kilograms of Fluorescein, an organic non-toxic powdered dye.

and also in 2023:

Venice authorities investigate after canal turns fluorescent green

https://abc7.com/post/rialto-bridge-grand-canal-venice-green-water-italy/13312215/