When the Emerald City and the Rose City go at it, from the outside it must look like a silly sibling feud between two hippies wearing REI chic. The two laid-back cultures maintain the most heated soccer rivalry in the country; on the men’s side with the Seattle Sounders and Portland Timbers, and now on the women’s side as well with the Seattle Reign versus the Portland Thorns. Admittedly, some concessions can be made. Seattle continues to top the list of most literate cities, but can’t boast anything to rival Portland’s Powell’s Books. Portland has Light Rail, but Seattle has free parking on Sundays. Seattleites may allow the superiority of Voodoo Doughnuts, but will never compromise on Tom Douglas and Thierry Rautureau. Can Portland really match the view of the Cascades to the east, the Olympics to the west and the Puget Sound in between? Seattle has crabbers from the Deadliest Catch wandering Ballard and Brandi Carlile playing Jimi Hendrix with Mike McCready backed by the Seattle Symphony at Benaroya Hall. Is it any real competition? Today on The Conversation , we explore the I-5 rivalry between the two cities and why these two ideologically-similar urban centers love to take each other down.