The Samurai Bridge is a long, grey bridge with two pillars in the middle. It also features a large gate with the kanji for an ancient currency unit "銖". The Samurai Bridge is located close to the Land of Snow and the Hidden Cloud Village. There is also two Rogue Ninja (160) and a Hawk boss (700) near the bridge.
Obito/Kakashi's Kamui can be found on one of the main gate pillars and it has a 50% chance of spawning every two and a half hours.
Hawk Summoning on the other hand, spawns on one of the two middle pillars every 1 hour and 30 minutes.
The bridge where after the Five Kage Summit, Tobi fights Danzo Shimura and where Sasuke Uchiha kills Danzo. (Naruto: Chapter 481, Narutopedia)