SEATTLE (AP) — The Cowlitz Indian Tribe is opening its new $510 million casino this week, an effort years in the making.

While Cowlitz officials hope the complex will draw some 4.5 million visitors, providing an economic boon to the tribe and the region, others are not so optimistic.

The Confederated Tribes of the Grand Ronde own the Spirit Mountain Casino in Oregon's Coast Range, and they fear Spirit Mountain could lose 41 percent of its revenue when the Cowlitz casino opens Monday near La Center, Washington.

Cowlitz Tribal Chairman William Iyall told the Seattle Times that opening day marks a triumphant moment for the Cowlitz Indian Tribe and signifies the end of a 160-year journey back to the tribe's homeland.

The tribe refused in 1855 to sign a treaty and move into a proposed reservation site. It took decades of campaigning to persuade the federal Interior Department in 2000 to grant the Cowlitz legal status as a tribe.