People have been leaving their creative mark on the walls of the streets for thousands of years - the oldest known cave paintings date back from more than 40,000 years ago. Today, those etchings have blossomed into a worldwide phenomenon of street art.
Adorning urban spaces across the globe, this form of art is often interwoven with the history and culture of a place and offers an eye-opening way to explore a destination.
Introducing: Part 2: The Best Cities To Explore Street Art...
Like many country's, Portugal's relationship with street art is grounded in politics; the art form emerges as a means to revolt against the right-wing dictatorship that controlled the country for the first half of the 20th century.
Today, it continues to flourish with Lisbon's landscape of contemporary buildings and medieval structures providing ample canvas. Most walls in lively Bairro Alto - particularly Calcada da Gloria - are drenched in design. Expect a mixture of artworks poking fun at pop culture crawling up the side of a high rise building.
Street art probably isn't the first thing that springs to mind when you think of Krakow, but this historical city has a longstanding tradition of graphic art.
Stroll through the city's centre and you'll soon happen upon masterpieces big and small, thanks to a government who has embraced the creative movement with open arms.
Commissioning murals to transform the grey walls of the apartment blocks, these colossal pieces draw a major crowd. Works by duo: Etam Cru stretch up buildings all across Poland; the pair's distinctive style is recognisable by its blend of modern design with traditional motifs which are derived from Polish folklore.
With a penchant for restoring derelict buildings and a soft spot for breaking the rules, it makes sense that Berlin is the most tagged city in Europe.
Whilst the German capital is known for its constantly evolving cityscape, unsurprisingly its sense of history runs deep. Nowhere is this relationship of past and present more tangible than in the murals of The East Side Gallery.
Whilst the famous Fraternal Kiss is worth a visit, walking the entire 1.3km stretch is equally of vital viewing. Over 100 murals were painted after the wall came down in 1989, transforming this past symbol of division into a national symbol of creativity and spirit.
SÃO PAULO, BRAZIL
The financial hub of Brazil, São Paulo is an urban jungle of skyscrapers and concrete pathways. Injecting some colour into this monotone landscape, local artists have taken to sketching murals and creative masterpieces across the city.
Head first for Beco de Batman in the Vila Madalena neighbourhood; along this narrow alleyway, each artist actually owns the wall on which they work. More fine art than street art, you'll find grander designs and large-scale murals in the neighbouring Pinheiros.
Make sure to visit on a Saturday when Benedito Calixto Square is filled with artisans peddling their wares.