I used to hate graffiti. It was such an eye sore and ruined, IMHO, beautiful buildings, bridges, etc.
But street art has risen to a new level over the decades. Much of it is now museum worthy. Here are some examples we came across in Brooklyn, New York:
What amazing graffiti have you come across?
It’s only a small graffiti but I absolutely love this in San Carlos in Costa Rica.
We love to visit a resort called Tabacon in the Arenal region and I always use this little rat as a distance marker so I know how much longer we have left to drive! 
Amazing @anon47943759! You almost don’t see the guy sitting on the bench, there’s so much else that catches your eyes!
So cute, and I love that you use it as a landmark @Samox24.
Wow! Now that is creative!
On a sit in Victoria, British Columbia, Canada 
A competition with about 20 artists all working only in chalks. I was fascinated by their talent. Yes, the last one is also on a flat surface.
@Snowbird Wow!
Saw these on the Sniper Tower in Mostar, Bosnia and Herzegovina, you can still see the bullet holes left as a reminder so never to be repeated.
Do you recognise this fine actor?
Spotted him in Pocono Summit, Pennsylvania but was also lucky enough to spot the real Mr Nicholson whilst driving along Mulholland Drive in LA 
… & spotted this Banksy whilst in Venice! 
Every September in Manchester UK, there is a street art competition. 20 or so street artists are given public spaces to create a piece and the results are phenomenal
@Colin there is also an annual street art festival in Cheltenham
https://www.cheltenhampaintfestival.co.uk/
