I have been working at the same location for 16 years and my employer decided to move me to a different location without valid reason and notice. Can they do that legally?

No, your employer is not allowed to change your locations and this would constitute a clear constructive dismissal entitling you to a severance package. Please use the following link to determine what a fair package would be in your circumstances (severancepaycalculator.com/) and then contact us at the number below for a consultation with a lawyer to discuss your situation.