A walkway system for a roof, the walkway system comprising a first fastening portion comprising at least one first fastening means for fastening the first fastening portion to a first roof structure of a roof and at least one first attachment means for attaching the first fastening portion to a first walking tread, wherein the first fastening portion further comprises a supporting portion configured to support the first fastening portion on a second roof structure; a second fastening portion comprising at least one second fastening means for fastening the second fastening portion to the first roof structure of the roof and at least one second attachment means for attaching the second fastening portion to the first walking tread, wherein the second fastening portion further comprises a supporting portion configured to support the second fastening portion on the second roof structure; a third fastening portion comprising at least one third fastening means for fastening the third fastening portion to the second roof structure of the roof and at least one third attachment means for attaching the third fastening portion to the first walking tread; and a fourth fastening portion comprising at least one fourth fastening means for fastening the fourth fastening portion to the second roof structure of the roof and at least one fourth attachment means for attaching the fourth fastening portion to the first walking tread, wherein the third fastening portion is further attached to a second walking tread and the fourth fastening portion is further attached to the second walking tread, characterized in that the first walking tread and the second walking tread extend at different heights to form steps. a first fastening portion comprising at least one first fastening means for fastening the first fastening portion to a first roof structure of a roof and at least one first attachment means for attaching the first fastening portion to a first walking tread, wherein the first fastening portion further comprises a supporting portion configured to support the first fastening portion on a second roof structure; a second fastening portion comprising at least one second fastening means for fastening the second fastening portion to the first roof structure of the roof and at least one second attachment means for attaching the second fastening portion to the first walking tread, wherein the second fastening portion further comprises a supporting portion configured to support the second fastening portion on the second roof structure; a third fastening portion comprising at least one third fastening means for fastening the third fastening portion to the second roof structure of the roof and at least one third attachment means for attaching the third fastening portion to the first walking tread; and a fourth fastening portion comprising at least one fourth fastening means for fastening the fourth fastening portion to the second roof structure of the roof and at least one fourth attachment means for attaching the fourth fastening portion to the first walking tread, wherein the third fastening portion is further attached to a second walking tread and the fourth fastening portion is further attached to the second walking tread, characterized in that the first walking tread and the second walking tread extend at different heights to form steps.