 Over the years , the city has been home to other large corporations in the central United States , making Denver a key trade point for the country . Several well @-@ known companies originated in or have relocated to Denver . William Ainsworth opened the Denver Instrument Company in 1895 to make analytical balances for gold <unk> . Its factory is now in Arvada . <unk> ( NYSE : <unk> ) — the largest owner and operator of apartment communities in the United States , with approximately 870 communities comprising nearly 136 @,@ 000 units in 44 states — is headquartered in Denver , employing approximately 3 @,@ 500 people . Also Samsonite Corp. , the world 's largest luggage manufacturer , began in Denver in 1910 as <unk> Trunk Manufacturing Company , but Samsonite closed its NE Denver factory in 2001 , and moved its headquarters to Massachusetts after a change of ownership in 2006 . The Mountain States Telephone & Telegraph Company , founded in Denver in 1911 , is now a part of telecommunications giant CenturyLink . 
