Tampa's old city hall is celebrating a historic birthday. The building turns 100 years old Sunday.

"Wow, 100 years old, that's awesome," said visitor MaryAnn Gravely. 

Local architect M. Leo Elliot designed the ornate structure. Completed on August 30, 1915, Tampa's old city hall was once the tallest building in downtown.

"They built city hall for a variety of reasons," said Tampa Bay History Museum Curator Rodney Kite-Powell. "They needed the extra space, they also were able to make a statement architecturally that Tampa was a growing city and had reached a level of status that it could have a really attractive government building."

The building has several interesting features, including the clock tower that's named after "Hortense," a resident.

During construction, city officials also placed a time capsule behind the 1915 cornerstone of the building.

That copper box is believed to contain century-old treasures. Kite-Powell is eager to see what is inside the capsule.

"I think 100 years is a great even number to open it on, so I'm hoping for that," Kite-Powell laughed.

Unfortunately, Tampa's mayor said because of the expense, the time capsule probably won't be opened this year.

Because of it's age the building is undergoing renovations. The mayor has requested more money in next year's budget for additional repairs.