With heads craned back and eyes skyward, visitors to the Gateway Arch offer plenty of praise for the sleek, gleaming monument that towers over the western bank of the Mississippi River.

But when they turn their heads toward the surrounding riverfront, they pick their words a little more carefully: It's nice enough, many say. Pleasant. Then they often get back in their cars and head on their way.

A movement is afoot to see that change.

A team is developing a plan for this famous American riverfront -- the 11/2-mile stretch between the Eads and Poplar Street bridges just east of Eero Saarinen's stainless steel masterpiece.

The development team includes the HOK Planning Group, which already has designed greenway and streetscape projects in the area. The lead designer is Diana Balmori of the New York-based Balmori Associates Inc. She helped write "Saarinen House and Garden: A Total Work of Art," a book about the house in Michigan designed by Saarinen's father, architect Eliel Saarinen.

Balmori recently reviewed Eero Saarinen's sketches for the Arch, which she calls "such a beautiful thing."

But, the riverfront itself, now that's a different matter. "As it is currently? It's terrible. It's not used. It's not good to look at, and it's not inviting."

The Arch and its park grounds are outside of the area to be redeveloped, and new choices will not compete with the world-famous design, planners said.

They also said the relatively undeveloped riverfront provides plenty of opportunity.

"There's a tremendous canvas there from which to paint the painting," said Rollin Stanley, St. Louis director of planning and urban design.

This stretch of riverfront played a crucial role in the city's development.

Here, Pierre Laclede chose to build a fur trading post in 1764 that would become St. Louis. Years later, the village turned into a bustling commercial center, where goods from the east would head to points west, first by boat and later by train.

The Eads Bridge, an architectural marvel that opened in 1874, carried trains across the Mississippi River between Illinois and Missouri. But over the decades, the city turned its back on the river, leading to decrepit buildings along the riverfront.

"It's at that point a group of civic leaders decided something needs to be done," said Robert Archibald, president of the Missouri Historical Society.

Led by lawyer Luther Ely Smith, a committee formed in 1933 for a monument to recognize St. Louis's role in westward expansion with a park paying tribute to Thomas Jefferson.

Crumbling riverfront buildings were demolished.

And in a competition that began in 1947, Saarinen's arch design was selected as a monument to the spirit of western pioneers. Arch construction ran from 1963 to in 1965, costing less than $15 million.

These days, to reach the riverfront, steps known as the Grand Staircase lead visitors on the Arch grounds at the Jefferson National Expansion Memorial park down to Leonor K. Sullivan Boulevard. But a walk right next to the river is no easy feat. A steep, cobblestone parking lot along the bank is usually filled with cars.

Two well-known riverboats -- the Tom Sawyer and Becky Thatcher -- pace the river. At their dock, ragtime music is piped into the air, drawing visitors to take a narrated tour up and down a stretch of the Mississippi, as working barges churn past.

The riverfront's future look remains to be decided. Possible additions include a permanent spot to rent bicycles, new dining areas, a place to stage concerts, permanent washrooms and the possible use of the river as a design element. The hope is to liven up the stretch without making it too commercial and to educate visitors about the working aspect of the river while pointing out famous features, such as the Eads Bridge.

Designers also want to pursue plans to better link the Arch grounds to the region, especially to make the walk more welcoming for pedestrians.

"I almost got hit crossing that street," said Tony Knight, 18, pointing to the busy exchange that separates the Arch grounds from downtown.

He and other Arch visitors proposed several riverfront changes, including the addition of maps to lead them to surrounding places and outdoor stations where people can work out.

Changes will have to be made along a riverfront prone to flooding, an aspect designers will consider. But events in recent years along the riverfront -- such as popular free concerts last summer -- have fueled interest.

Development of the plan should take about a year, and public opinions will be sought. Organizers said the hope is that the development could be completed in five years or less.

The Gateway Arch is a draw, but developers are considering a bicycle rental area and a place to stage concerts.