 Ramba uchinyora ndima iyi - David Thompson ndiye akanga ari muEurope wokutanga kufamba nomugungwa achitevedza rwizi rwaColumbia. Pakati peKettle Falls 3 July 1811 neJunction yeColumbia neSnake Rivers 9 July aifamba munyika yakanga isati yamboshanyirwa nevaEurope, uye akatora nguva yekushanyira misha iri munzira yekugadzira hukama hwakanaka, akabatsirwa nehuwandu hwakawanda hwefodya. Muna 1805 Lewis naClarkrakanga raburuka rwizi runonzi Snake, uye ipapo rakaramba richidzika rwizi runonzi Columbia. Paakasvika pamharadzano yacho, Thompson akamisa danda pamwe chete netsamba yaitaura kuti nyika yacho yaiva yeGreat Britain uye yaitaura nezvechinangwa cheNorth West Company chokuvaka nzvimbo yokutengesera panzvimbo yacho. Chiziviso ichi chakawanikwa gare gare gore iroro nevashandi vekambani yeAstor vachitsvaka kutanga nzvimbo yemukati yemvere, zvichiita kuti vasarudze nzvimbo iri kuchamhembe kuFort Okanogan. The North West Company yakatanga nzvimbo yayo yeFort Nez Percés pedyo neSnake River confluence makore akawanda gare gare. Achipfuurira achidzika neColumbia, Thompson akapfuura Celilo Falls, anenge achirasikirwa nekano pamatombo, uye akafamba achitenderera mapopoma eThe Dalles neCascades Rapids. Musi wa14 Chikunguru 1811, Thompson akasvika paFort Astoria pamuromo peColumbia, achisvika mwedzi miviri mushure mekunge ngarava yePacific Fur Company, iyo Tonquin. 