ST. LOUIS -- A long-awaited extension of Grant's Trail near St. Louis is moving ahead, with the promise of what will become a continuous 17-mile route for bicyclists, walkers and runners.

Adding two miles to the trail to link it to the River Des Peres Greenway will cost $10.2 million, the St. Louis Post-Dispatch reported. That extension includes adding two bridges and a tunnel.

Great Rivers Greenway is offering $7.2 million for the work and seeking a $3 million federal grant to cover the remainder. That entity's board has voted to pursue the grant through the East-West Gateway Council of Governments, which allocates federal dollars in the St. Louis region.

"For us to pour $10 million into one project would draw resources from the rest of the region," said Emma Klues, Green Rivers Greenway's spokeswoman.

Grant's Trail, which crosses south St. Louis County, is 8.25 miles and among the busiest local trails, with more than 750,000 users per year.

As a cyclist who rides the trail once a week, Laura Schulz of the St. Louis suburb of Webster Groves, Missouri, welcomes the idea of expanding it, believing it could spread users out over a longer distance. Another perk: Cyclists could go from St. Louis County into St. Louis city without venturing onto streets to add miles to their rides.

"Most people who want to go out for a serious ride want to get in 20 or 25 miles or more," Schulz said.

The continuous trail could be even longer someday, with plans to grow the River Des Peres Greenway to 11 miles between Forest Park and the Mississippi River.