As a new year begins in Chicago, the upcoming Obama Presidential Center appears to be no closer to breaking ground on the city’s South Side. The Obama Foundation first announced its Jackson Park site nearly four years ago, but there is no firm timeline for when the controversial center will start construction—let alone open.

The Obama Presidential Center gained city approval in spring 2018. At the time, organizers said they hoped to break ground later that year and open sometime in 2021. Since then, the Obama Foundation has yet to release an updated timetable to the public.

The construction process has been complicated by multiple factors, most notably an ongoing federal review, triggered by the proposed center’s location in a historic park designed by Frederick Law Olmsted and Calvert Vaux and the site of the World’s Columbian Exposition in 1893. Until that process is complete, work cannot begin.

“We appreciate the thorough analysis being conducted by the federal agencies and the participation of dozens of stakeholders around the city,” said a foundation spokesperson in a statement to the Chicago Tribune. “We join many in Chicago in feeling the urgency to bring the OPC to the South Side and are eager to see this process through its completion.”

In 2018, a nonprofit environmental group called Protect Our Parks filed a federal lawsuit against the $500 million development. Although a judge later dismissed the suit, the decision could be appealed. The legal challenge also revealed alternate sites considered by the foundation—including private land that could have avoided the level of scrutiny and controversy of its location in Jackson Park.

“If the Obama Presidential Center had chosen a privately-owned development site... it would be open for visitors today,” wrote advocacy group Preservation Chicago. “The second choice option is across from Washington Park. It requires no federal review, no massive road rebuilding, and no special deals with [the] city of Chicago.”