About a decade ago I was thinking about spider-man swinging down a NY Avenue, his web going from building on one side to a building on the other (you know the scenes I&#x27;m talking about), and I realized it just couldn&#x27;t be. Pretty quickly he&#x27;d touch the ground. Gave a good explanation to my friends and half of them didn&#x27;t get it, the other half thought I was wrong&#x2F;stupid because of course you can swing down an avenue  like spiderman. Now I got the itch to call these same friends and tell them about these bridges. Thanks!