There's been royal visits and days to celebrate.
Why not have a look back yourself at some of the town's factories which hold a place in the Sunderland Echo archives.
1. Princess Diana visited the Fisher Price toy factory in Peterlee in 1983.
Princess Diana visited the Fisher Price toy factory in Peterlee in 1983.
2. A leading glass supplier and here it is 20 years ago.
A leading glass supplier and here it is 20 years ago.
3. The Dewhirst factory and shop, on the North West Industrial Estate, as it looked in 2003.
The Dewhirst factory and shop, on the North West Industrial Estate, as it looked in 2003.
4. A 20-year-old photo of textiles specialist Sara Lee Courtalds on the North West Industrial Estate.
A 20-year-old photo of textiles specialist Sara Lee Courtalds on the North West Industrial Estate.