how to delete a guest after creating it with virt-install

I created a KVM guest from the command line with virt-install where I used the command line options --disk pool=vg0,size=20 and --name virt1.example.com.

How can I delete this KVM guest from the command line? I don't need it anymore.

Just for the record the whole command line was

virt-install --debug --hvm --vnc --name virt1.example.com --os-type=linux --os-variant=rhel6 --pxe --network network=default,model=e1000,mac=02:54:00:13:be:e4 --disk pool=vg0,size=20 --ram 1024 --vcpus=1 

and here is some extra information

[root@server ~]# virsh vol-list vg0
Name                 Path                                    
-----------------------------------------
lv0                  /dev/vg0/lv0                            
lv_swap              /dev/vg0/lv_swap                        
virt1.example.com.img /dev/vg0/virt1.example.com.img  

[root@server ~]# virsh list
 Id Name                 State
----------------------------------
  3 virt1.example.com running

Update

Running these three commands seems to remove the installed KVM

virsh destroy virt1.example.com
virsh undefine virt1.example.com
virsh vol-delete --pool vg0 virt1.example.com.img

For more details see the terminal session:

[root@server ~]# virsh list --all
 Id Name                 State
----------------------------------
 3 virt1.example.com running

[root@server ~]# virsh undefine virt1.example.com
error: Failed to undefine domain virt1.example.com
error: Requested operation is not valid: cannot delete active domain

[root@server ~]# virsh destroy virt1.example.com
Domain virt1.example.com destroyed

[root@server ~]# virsh list --all
 Id Name                 State
----------------------------------
  - virt1.example.com shut off

[root@server ~]# virsh undefine virt1.example.com
Domain virt1.example.com has been undefined

[root@server ~]# virsh list --all
 Id Name                 State
----------------------------------

[root@server ~]# virsh vol-list --pool vg0
Name                 Path                                    
-----------------------------------------
lv0                  /dev/vg0/lv0                            
lv_swap              /dev/vg0/lv_swap                        
virt1.example.com.img /dev/vg0/virt1.example.com.img  

[root@server ~]# virsh vol-delete --pool vg0 virt1.example.com.img
Vol virt1.example.com.img deleted

[root@server ~]# virsh vol-list --pool vg0
Name                 Path                                    
-----------------------------------------
lv0                  /dev/vg0/lv0                            
lv_swap              /dev/vg0/lv_swap                        

[root@server ~]# cat /etc/issue
CentOS Linux release 6.0 (Final)
Kernel \r on an \m

[root@server ~]# virsh --version
0.8.1