In order to conserve the limited bandwidth available, ISO images are not downloadable from mirror.centos.org

http://us.mirror.nsec.pt/centos/6.10/isos/i386/
http://mirror.cs.vt.edu/pub/CentOS/6.10/isos/i386/
http://mirror.cogentco.com/pub/linux/centos/6.10/isos/i386/
http://mirror.centos.iad1.serverforge.org/6.10/isos/i386/
http://mirror.vtti.vt.edu/centos/6.10/isos/i386/
http://repo1.ash.innoscale.net/centos/6.10/isos/i386/
http://mirror.ash.fastserv.com/centos/6.10/isos/i386/
http://centos4.zswap.net/6.10/isos/i386/
http://mirror.vcu.edu/pub/gnu_linux/centos/6.10/isos/i386/
http://mirrors.advancedhosters.com/centos/6.10/isos/i386/
http://repos-va.psychz.net/centos/6.10/isos/i386/

http://mirror.rackspace.com/CentOS/6.10/isos/i386/
http://mirror.tzulo.com/centos/6.10/isos/i386/
http://mirror.tocici.com/centos/6.10/isos/i386/
http://mirrors.umflint.edu/CentOS/6.10/isos/i386/
http://mirror.dal.nexril.net/centos/6.10/isos/i386/
http://mirrors.xmission.com/centos/6.10/isos/i386/
http://mirror.mia11.us.leaseweb.net/centos/6.10/isos/i386/
http://mirrors.oit.uci.edu/centos/6.10/isos/i386/
http://mirror.oss.ou.edu/centos/6.10/isos/i386/
http://mirrors.rit.edu/centos/6.10/isos/i386/
http://mirrors.tummy.com/mirrors/CentOS/6.10/isos/i386/
http://mirror.grid.uchicago.edu/pub/linux/centos/6.10/isos/i386/
http://mirrors.cat.pdx.edu/centos/6.10/isos/i386/
http://mirror.genesisadaptive.com/centos/6.10/isos/i386/
http://mirrors.unifiedlayer.com/centos/6.10/isos/i386/
http://mirror.sjc02.svwh.net/centos/6.10/isos/i386/
http://mirror.web-ster.com/centos/6.10/isos/i386/
http://mirror.mi.incx.net/centos/6.10/isos/i386/
http://linux.mirrors.es.net/centos/6.10/isos/i386/
+ others, see the full list of mirrors: https://www.centos.org/download/mirrors/

Mirrors verified Wed Apr 8 00:02:48 2020 UTC

You can also download the ISO images using bittorrent, a peer-to-peer file sharing protocol. The .torrent files can be found from CentOS mirrors. Various bittorrent clients are available, including (in no particular order of preference): utorrent, vuze (Azureus), BitTorrent, Deluge, ctorrent, ktorrent, rtorrent and transmission. Packaged copies of various torrent clients for CentOS can be found in the repositories listed in the following wiki article: https://wiki.centos.org/AdditionalResources/Repositories