Rising spectacularly on a bluff where the Mississippi and Minnesota rivers meet, Fort Snelling is one of the most important historic sites in the state, and considered sacred ground by American Indians.

That landscape, familiar to thousands of Minnesotans, could change for the first time in more than a half century. Plans for the proposed Riverview Corridor streetcar line call for enlarging a tunnel beneath the historic fort, or further burrowing near it to build a new one.

The 12-mile streetcar project, still in the early planning stages, is slated to connect downtown St. Paul to the Minneapolis-St. Paul International Airport and the Mall of America. Service isn't expected to begin until 2032.

But the planned bisection of the fort's lower post has prompted concern among historians and others. Some wonder how a bigger tunnel might affect Minnesota's first National Historic Landmark — and what might be unearthed in the process of building it.

"We don't want any history damaged in the long term," said David Kelliher, director of public policy and community relations for the Minnesota Historical Society (MNHS), which manages Historic Fort Snelling, its official designation. "It is very early in the planning process, but we do have concerns about a potential route that would come very close to very important historic resources."

Ramsey County transit planners insist a yearslong and thorough environmental review process will answer most all questions and care will be taken to ensure the fort is not compromised.

"All this work is being done to help nail down some answers to questions," said Mike Rogers, transit project manager for the Ramsey County Regional Railroad Authority. "Where are the footings for the buildings? Where are the sacred sites? Where are other archaeological or cultural sites so you can avoid them or mitigate them?"

Currently, the Metropolitan Council is considering whether to include the Riverview Corridor in its long-term transportation plan for the metro — a move that would qualify the line for possible federal funding. The project is expected to cost about $2 billion, with planners hoping the federal government will cover about half the tab.

The regional planning body plans to hold a series of public meetings later this year and in early 2019.

Tragedy and heartbreak

Historic Fort Snelling is located on Dakota homeland known as Bdote, meaning "where two waters come together." The Dakota people consider it their spiritual and cultural provenance, an area with history spanning 10,000 years.

"If you look at the history of the whole area as a clock, the fort was built in the very last few minutes," said Joe D. Horse Capture, director of MNHS' Native American Initiatives. "There are multiple layers of history and meaning to native people — sacred space and, of course, a lot of tragedy and heartbreak."

The fort itself was completed in 1825 and decommissioned following World War II. Its history represents the broader story of the state's founding — touching on trade, the military, veterans, slaves and the U.S.-Dakota War of 1862, according to the Historical Society.

The enclosed fort consists of several buildings, including the Round Tower, one of the original structures that served as a defense post. In 1956, the Minnesota Department of Transportation (MnDOT) proposed building a highway through part of the old fort with a cloverleaf encircling and choking off the Round Tower.

Considerable public outcry prompted then-Gov. Orville Freeman to convince the highway department to instead build under the fort — a little-known tunnel on Highway 5 that still exists today. The tunnel has figured prominently in conversations about the Riverview Corridor's proposed route — whether it should be enlarged, or if a new portal should be built alongside it.

Either way, the historic fort looms above. After the midcentury cloverleaf kerfuffle, an extensive archaeology project at the fort continued through the early 1980s. The work unearthed an estimated half-million artifacts, which helped to reconstruct nearly two dozen buildings at the fort's lower post.

A new river crossing?

Discussion about the Riverview Corridor, which is slated to travel from Union Depot in downtown St. Paul along W. 7th Street, often concentrated on where the streetcar would cross the Mississippi River.

When a possible route across the Ford Parkway bridge presented technical and engineering challenges, an advisory committee opted for a streetcar to cross the Mississippi River on or near the Hwy. 5 bridge. Along that route, it would travel to the existing Blue Line Fort Snelling station, and then share light-rail tracks to the airport and the Bloomington megamall.

The National Park Service, which oversees land on both sides of the Mississippi River at Fort Snelling, called for the crossing to span an existing bridge, or a new one adjacent to it — as opposed to building a different one somewhere else.

Rogers, of Ramsey County, says building a streetcar-only bridge with bicycle and pedestrian amenities alongside the current Hwy. 5 span, which was reconstructed in 2016 for nearly $14 million, is a possibility that will be further studied.

Much of the public discussion in more than 100 public hearings held in recent years about the Riverview Corridor line has centered on the effect the streetcar will have on small businesses and residences along W. 7th Street.

But in comments solicited from the public, one person wrote that the Fort Snelling tunnel would be "an obvious desecration and contrary to decades of work to reclaim, restore and protect the historic area — and at enormous additional cost to the project."

For now, officials from the Historical Society say they will continue to follow the streetcar's planning process closely. They're also mindful that the line could present positive attributes for the site, including a proposed streetcar stop near the lower fort, and the prospect of better unifying the Fort Snelling Memorial Chapel with the rest of the campus.

"There are positive possibilities with the landscape there," Kelliher said. "But we might as well ask these questions now."

Janet Moore • 612-673-7752 @MooreStrib

Correction: An earlier version of this story had an outdated title for Joe D. Horse Capture at the Minnesota Historical Society.