Depending on the year places marked different.

The attachment of the bumpers at the first-and second-generation Citroen C1 is almost identical to the Peugeot 107 and Peugeot 108, respectively.

See:

How to remove front and rear bumper Peugeot 107 (Citroen C1 2005-2014)

How to remove front and rear bumper Peugeot 108 (after the Citroen C1 2014)