Now you can actually see how travelers crisscross the globe. 

Michael Markieta, a Canadian GIS consultant for the global engineering and design firm Arup, spent a year tracing some 58,000 routes on major and regional airlines around the globe using geographical information systems technology to create flight path graphics. 

Marketa's map shows relatively faint blue lines for each individual route and bright white nodes where multiple routes intersect or overlap.

While the world's busiest airport is in Atlanta, Georgia, Frankfurt International was found to have the most connections. Sao Paulo, Beijing, Sydney and Cairo were the other busiest airports by continent.

Markieta began to work on visualizations in his spare time, using  the data at the open-source project openflights.org. He hopes that the project will prove useful to researchers in various fields needing to understand more about global connectivity. 

Arup contends that climate change is a threat to the aviation industry, with 150 airports at risk of sea level rise.