You can expand a domain by adding neighbouring lands. The expansion of a domain is limited according to its population. You can not expand a domain if its expansion capacity is lesser than its area in acres. This information can be found on the unit management page. Expansion on an existing domain is legitimate as long as it is more than 48 arpents from its centre. It becomes impossible less than 16 arpents from the centre or if the expansion area includes [URL=/help/bld/wall]fortifications[/URL].