The United States is getting ready to celebrate its 250th birthday! In 2026, the country will mark 250 years of independence. To commemorate this special day, a time capsule will be buried in Philadelphia. This capsule will show future Americans what life was like in 2026. All 50 states, Washington D.C., and U.S. territories contributed to this project. Some states, like Utah, contributed a lot. Utah sent 100 historical cards, 13 coins, 8 documents, 8 badges, 2 granite disks, and a brochure. Other states sent just one or two items. Arkansas sent a diamond, while Maine added a bone from an endangered whale. Wisconsin sent a feather from an eagle named 'Old Abe' that served with Union soldiers during the American Civil War. California sent a high-tech package that included a computer chip and a prediction of what the state might be like in 2276. Choosing the items was just part of the task. Making sure they would survive for 250 years underground was an even bigger challenge. This task was given to Michael Berilla and the National Institute of Standards and Technology (NIST) team. Water is one of the biggest threats to buried time capsules. Even small leaks can destroy the contents. To solve this problem, Berilla and his team made the capsule out of stainless steel and created a waterproof barrier using a soft metal to fill small gaps. They also chose a cylindrical design instead of a traditional box. This is because boxes can crack at the corners over time and increase the risk of moisture seeping in. A heavy steel lid will also be placed on top to provide extra protection. 'The time capsule could get water in it because Philadelphia is supposed to be 6 feet underwater,' said Berilla. The capsule will be buried near Independence Hall in Philadelphia in 2026. This is where the Declaration of Independence was adopted in 1776. To help future generations find the site, it will be marked with a special granite and steel sculpture. It's shaped like a big segmented snake, inspired by Benjamin Franklin's famous 1754 'Join or Die' cartoon. The National Park Service has recorded the site in official documents and will pass it on to future park rangers. When the capsule is finally opened in 2276, the first items inside will be a photo of the engineering team and a letter from Berilla. 'Greetings from the hearts and hands that lived and breathed in 2026. We will be long gone by then, but our commitment, pride, and hopes for our world will live on in this steel,' it says.