Feb. 04ā€“Archaeologists who for months have been uncovering mounting evidence of an ancient and extensive Native American village in the middle of downtown Miami have concluded itā€™s likely one of the most significant prehistoric sites in the United States.

The archaeologists, under the direction of veteran South Florida archaeologist Bob Carr, have so far painstakingly dug up eight large circles comprised of uniformly carved holes in the native limestone that they believe to be foundation holes for Tequesta Indian dwellings dating as far back as 2,000 years.

They have also discovered linear, parallel arrangements of hundreds of such postholes stretching across the site that Carr hypothesizes mark the foundation for other structures, possibly boardwalks connecting the dwellings. The village site borders a rocky outcropping that his team has concluded was the original natural shoreline at the confluence of Biscayne Bay and the Miami River, a spot long ago occluded by fill.

ā€œWhatā€™s unusual and unique about the site is that itā€™s this huge chunk of land where a major part of this ancient Tequesta village site is preserved,ā€ Carr said in an interview. ā€œItā€™s one of the earliest urban plans in eastern North America. You can actually see this extraordinary configuration of these buildings and structures.ā€

The finds, which have not been widely publicized, have placed public officials and a big downtown developer in a major quandary. The Tequesta village site covers roughly half of a long-vacant, two-acre city block on the north side of the river where the developer, MDM Development Group, plans to build movie theaters, restaurants and a 34-story hotel. The project would cover most of the block, including the full archaeological site.

The city of Miami granted MDM zoning and development approvals for the Met Square project, though not a final building permit, before the full scope of the archaeological finds was known or understood. The site has also yielded thousands of Tequesta artifacts, including bone and shell tools, as well as newly uncovered remnants of industrialist Henry Flaglerā€™s 1897 Royal Palm Hotel, which gave rise to the city of Miami.

State of Florida and Miami-Dade County historic-preservation officials are pressing the city to revisit the Met Square plans to consider possible alternatives that would salvage a portion of or even the full archaeological site. That could require a major, costly redesign of the Met Square project.

MDM, which already has leases, agreements and timetables for the theaters, restaurants and hotel, says it could be out a substantial amount of money if that happens. The developer has offered to carve out the limestone holding one or two of the larger circles on the site and display those in a planned public plaza. In recent weeks, MDM officials have discussed doing more in meetings with city and county planners and preservation officials, but have made no promises or commitments.

ā€œWe will do our utmost,ā€ MDM director Ian Swanson said Monday in an interview at the site. ā€œThere is no easy answer to this at all.ā€

While recognizing the siteā€™s importance, Swanson said there are still ā€œambiguitiesā€ over precisely what it was. He said the store of artifacts taken from the site and stored at the HistoryMiami museum will provide specialists and historians yearsā€™ worth of study and analysis.

Carr, who works for MDM, which by law must pay for the archaeological survey, said he has also recommended to his client that as much as possible of the site be preserved in place.

ā€œIf you have a necklace filled with pearls, what makes it valuable is its entirety, not four or five pearls,ā€ Carr said.

Preservationists note that MDM took a chance when it purchased the property a decade ago because it knew the site was inside a designated archaeological zone. Though the site was covered by an asphalt parking lot for 70 years, Carr and other archaeologists long suspected it was once part of a Tequesta village given previous finds of burial grounds and middens in the immediate vicinity.

The dilemma echoes the battle to save the Miami Circle, a set of postholes discovered by Carr in 1998 on the south bank of the river, opposite the recently uncovered Tequesta village site. Archaeologists concluded the circle marked the site of Tequesta council house or ceremonial structure dating back as far as 2,000 years.

After an international uproar, and facing a suit by preservationists, a developer who planned a condo on the site sold the property to the state for $27 million. It has since been turned into a park, though the circle was buried as a protective measure because the state lacked money to exhibit it properly.

The cityā€™s historic preservation board, which has legal authority over archaeological sites, is scheduled to receive a monthly update on the newest finds ā€” including the discovery of an eighth circle in the past several days ā€” at its regular meeting Tuesday. The board is also expected to set a special meeting within the next two weeks to debate what to do about the Tequesta site.

Preservationists and city board members say there is strong and growing support for measures to save and create a major exhibit around at least some of the archaeological site. State officials say it would likely earn National Historic Landmark status, like the Statue of Liberty and Miamiā€™s Freedom Tower. Some local officials and preservationists believe it might also qualify for designation as a UNESCO World Heritage site.

Making the site even more significant, they say, is the fact that Carrā€™s team has also uncovered artifacts and other elements from two later historic structures sandwiched over the Tequesta village at the site ā€” a well and artifacts from Fort Dallas, a mid-19th Century military fortification used during two of the Seminole Indian wars, and brick column bases and other traces of Flaglerā€™s hotel, which prompted the founding of the city of Miami.

ā€œItā€™s extremely important,ā€ said city preservation board member Gerald Marston of the site. ā€œIf they gave it a name, itā€™s the birthplace of Miami.ā€

Early finds on the site had been previously announced, including a circle Carr discovered in 2005 and dubbed the Royal Palm Circle after the Flagler Hotel. But the rest of the ensemble was discovered only in the past six months.

It was not until Miami-Dadeā€™s county archaeologist, Jeff Ransom, got wind of the recent finds in the fall that word began getting out, however. Carr acknowledges he had not notified the county and city of major finds as required, an oversight he said he has corrected.

Met Square is the fourth phase of MDMā€™s massive Met Miami development, which takes up four adjacent city blocks. Two other phases, a condo and a tower housing a Marriot Marquis hotel and offices, have been completed.

Carr found the remains of scores of Tequesta people in a burial ground under the third phase, a Whole Foods with a parking garage and residential tower, now under construction. The remains were reburied in an undisclosed location following Florida law.