Philadelphia will inter a 900-pound time capsule this week as part of the nationwide America250 commemoration, marking 250 years since the signing of the Declaration of Independence. The capsule, set to be buried 10 feet underground in a location secured against temperature changes and weather damage, reflects a broad spectrum of contributions from across the United States, including all 50 states, five territories, the District of Columbia, and branches of the federal government.
According to project officials, items within the capsule are maintained at about 35% relative humidity to balance preservation needs—preventing both desiccation and moisture damage. The capsule’s burial site was chosen for its stability, with experts noting that Philadelphia would need to be submerged by at least six feet of water for the capsule to potentially be compromised.
The contents of the time capsule emphasize diversity and hope for the future. Many submissions come in archival-quality boxes, with printed materials such as letters, postcards, posters, and poems stored separately in specialized compartments. States contributed a wide range of materials reflecting their unique histories and identities. For instance, New Hampshire included a Revolutionary War timeline brochure, while California offered an imaginative glimpse into the future by submitting an AI-generated prediction of what the state might look like 250 years hence—a future where highways have disappeared, grizzly bears have returned, and the state has joined with Oregon, Washington, and British Columbia to form a so-called “Pacific Federation.”
Several states submitted extensive and varied donations: Utah provided 100 historical cards, numerous coins, documents, pins, granite disks, and a booklet, whereas Arizona used nano-etching technology to inscribe the full text of the Declaration of Independence and the U.S. Constitution onto a stainless steel coin. Other contributions were more symbolic or naturalistic; Maine sent a bone from an endangered North Atlantic right whale, and Arkansas contributed a diamond.
Project manager Tom Medema, a retired National Park Service official, highlighted the open approach given to contributors. “There wasn’t a strict prescription,” he said, noting that states were free to represent themselves as they chose, which resulted in a fascinating variety of items.
Certain items were disallowed due to concerns about degradation or rust, with Maryland’s submission of Old Bay seasoning rejected. A Native American beaded artwork featuring elk hide was also reworked for preservation, substituting fabric for the hide.
While some inclusions acknowledge difficult aspects of American history and current challenges, the overarching tone remains optimistic. Medema described the project as inspiring for those involved. “There’s great hope in what this capsule represents,” he said.
This time capsule continues a tradition connected to America’s anniversaries. Previous capsules include the “Century Safe” buried in 1876 and opened in 1976 by President Gerald Ford, along with a bicentennial capsule stored at the National Archives slated to open in 2076. Another capsule, planned for the U.S. Capitol Visitor Center, is also underway.
To ensure future generations locate the America250 capsule in 2276, the National Park Service integrated detailed information about it into its long-term site management plans, and a capstone will mark its resting place.
Project lead Berilla reflected on the nation’s resilience, emphasizing diversity, creativity, and collaboration as defining traits of present-day America. Inside the capsule is a team photograph and a letter from Berilla, expressing hope for the future. “We will have long since returned to dust, but our devotion, pride, and unwavering hope for what our world could become are alive right here inside this steel,” he wrote. “We built this for you.”