A proposed 250-foot gilded arch championed by former President Donald Trump could undermine the historical significance of numerous sites in Washington, D.C., according to an assessment by the National Park Service (NPS). The report indicates that the arch's scale and location would disrupt "character-defining visual and spatial relationships" between historically important monuments and buildings.

The NPS report, released Monday, states the project area is situated within the Memorial Avenue Corridor cultural landscape, a significant historic designed landscape that extends between the Lincoln Memorial in Washington and Arlington National Cemetery in Virginia. The report highlights that the arch would interrupt the sightline alignment between the Lincoln Memorial, Memorial Bridge, and Arlington House, the former home of Confederate Gen. Robert E. Lee.

This alignment was intended to "physically and symbolically unite North and South through a coordinated monumental composition across the Potomac River," the NPS noted. The report's findings present a challenge to a project that had been advancing through the approval process with initial endorsements from federal commissions appointed by Trump.

The proposed arch is one of several projects Trump has pursued to leave a lasting mark on the capital. Its potential to alter the city's visual landscape has already drawn opposition, including a lawsuit filed by a group of veterans and a historian. This legal challenge contends that the construction requires Congressional approval. Nicolas Sansone, an attorney with Public Citizen Litigation Group representing the plaintiffs, stated that authorization for a monument in the "core of Washington, D.C., on National Park Service land" must come from Congress.

The U.S. Commission of Fine Arts and the National Capital Area Planning Commission have both granted initial approvals for the arch's design and site. The National Capital Area Planning Commission is scheduled to revisit the matter in September. The NPS assessment appears to corroborate the plaintiffs' arguments regarding the potential impact on the symbolic and solemn nature of the area.