See: wiki.centos.org/Download

File version
CentOS Linux 7
release Based on RHEL Source (Version)
7 (1804). 7.5
7 (1708). 7.4
7 (1611). 7.3
7 (1511). 7.2
7 (1503). 7.1
7 (1406). 7
CentOS Linux 6
release Based on RHEL Source (Version)
6.10 6.10
6.9 6.9
6.8 6.8
6.7 6.7
6.6 6.6
6.5 6.5
6.4 6.4
6.3 6.3
6.2 6.2
6.1 6.1
6 6
CentOS Linux 5
release Based on RHEL Source (Version)
5.11 5.11
5.10 5.10
5.9 5.9
5.8 5.8
5.7 5.7
5.6 5.6
5.5 5.5
5.4 5.4
5.3 5.3
5.2 5.2
5.1 5.1
5 5
CentOS Linux 4
release Based on RHEL Source (Version)
4.9 4.9
4.8 4.8
4.7 4.7
4.6 4.6
4.5 4.5
4.4 4.4
4.3 4.3
4.2 4.2
4.1 4.1
4 4
CentOS Linux 3
release Based on RHEL Source (Version)
3.9 3.9
3.8 3.8
3.7 3.7
3.6 3.6
3.5 3.5
3.4 3.4
3.3 3.3
3.1 3.1
CentOS Linux 2.1
release Based on RHEL Source (Version)
2.1 2.1