Congress has sent to President Bush a bill that would establish the Lewis and Clark National Historical Park in Oregon and Washington state.

The measure would expand and rename Fort Clatsop National Memorial in Oregon in honor of explorers Meriwether Lewis and William Clark. It also would add three sites along the lower Columbia River, bringing the park for the first time into Washington state.

The Bush administration proposed the federal park in February, calling it a fitting way to mark the bicentennial of the pair's expedition seeking a northwest passage to the Pacific Ocean. The Senate gave the measure final congressional approval Sunday night.

The Lewis and Clark-led Corps of Discovery, a 33-member expedition, spent the winter of 1805-06 in Fort Clatsop, working on their journals and maps and making salt before starting the journey home.

A replica of the 50-by-50-foot Fort Clatsop, sponsored by the Clatsop County community, is the focus of the park, which is about five miles south of Astoria, Ore. The park also features a historic canoe landing.

The National Park Service said there were 251,872 recreation visitors to the Fort Clatsop park last year.

While the winter encampment was at Fort Clatsop, the expedition traveled widely over the region, making a two-state park appropriate, Interior Secretary Gale A. Norton said.

The park plan follows approval of a law two years ago to expand the Fort Clatsop memorial from 130 to 1,500 acres. The three new sites would add 560 more acres to the park.

"From minting new coins to printing commemorative stamps, Americans have already started celebrating the journey of Lewis and Clark," Sen. Gordon Smith (R-Ore.) said. "This bill will help us provide a fitting tribute to the explorers who opened up our nation."

The sites to be added to the park include the Station Camp site near McGowan, Wash., where Lewis and Clark camped before returning east in 1806, as well as the Megler Rest Area and Cape Disappointment State Park, formerly known as Fort Canby State Park.