![Looking upstream into Black Canyon toward Hoover Dam site showing outlet portals of four diversion tunnels Looking upstream into Black Canyon toward Hoover Dam site showing outlet portals of four diversion tunnels](https://l450v.alamy.com/450v/w5r7k1/looking-upstream-into-black-canyon-toward-hoover-dam-site-showing-outlet-portals-of-four-diversion-tunnels-and-blasting-in-outlet-valve-house-excavations-river-is-being-diverted-through-tunnels-3-4-scope-and-content-photograph-from-volume-two-of-a-series-of-photo-albums-documenting-the-construction-of-hoover-dam-boulder-city-nevada-w5r7k1.jpg)
Looking upstream into Black Canyon toward Hoover Dam site showing outlet portals of four diversion tunnels
![Looking upstream through Black Canyon toward Hoover Damsite showing condition after diversion of Colorado River. Lower levels of canyon choked with material blasted and stripped from canyon walls. Downstream rock barrier seen Looking upstream through Black Canyon toward Hoover Damsite showing condition after diversion of Colorado River. Lower levels of canyon choked with material blasted and stripped from canyon walls. Downstream rock barrier seen](https://c8.alamy.com/comp/TY8692/looking-upstream-through-black-canyon-toward-hoover-damsite-showing-condition-after-diversion-of-colorado-river-lower-levels-of-canyon-choked-with-material-blasted-and-stripped-from-canyon-walls-downstream-rock-barrier-seen-in-foreground-scope-and-content-photograph-from-volume-two-of-a-series-of-photo-albums-documenting-the-construction-of-hoover-dam-boulder-city-nevada-TY8692.jpg)
Looking upstream through Black Canyon toward Hoover Damsite showing condition after diversion of Colorado River. Lower levels of canyon choked with material blasted and stripped from canyon walls. Downstream rock barrier seen
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Hoover Synua Plus SY04 Aspirapolvere Scopa elettrica Tutto in 1, 550 W, 1.2 Litri, 79 Decibel, Plastica Robusta, Nero Luxor Lucido : Amazon.it: Casa e cucina
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