Friday is UN-Habitat's World Cities Day

Friday is the UN-Habitat's World Cities Day and Guardian Cities is hosting the World Cities Day Challenge, which will showcase 36 cities around the world and their best ideas.

From Guardian Cities:

We really want the whole day to be as interactive as possible, with heaps of discussion about how urban initiatives from some cities could inspire others – and in general how we can collaboratively build a better urban future. We're encouraging people to cheer on their city or grill the participants about the projects and initiatives they're representing.

We'll be covering the whole day on @guardiancities and the day's hashtag is #CitiesDay.

It will be interesting to see what the 36 "best ideas" are...

The cities:

• Auckland
• Bhubaneswar (India)
• Helsinki
• Tallinn
• Paris
• Johannesburg
• Manila
• Addis
• Hong Kong
• Ismir (Turkey)
• Beijing
• Fiskars
• Manchester
• Seville
• Istanbul\
• Brussels
• Kumasi (Ghana)
• Mumbai
• Florence
• Berlin
• Porto Alegre
• Nottingham
• London
• Croydon
• Toronto
• Indianapolis
• Barcelona
• Buffalo
• Mexico City
• Washington DC
• Bogota
• Chicago
• Calgary
• Monterrey
• South San Francisco
• Vancouver