Forts were framed for defence against land or sea forces, but useless against an air attack.

建筑城堡是为了防御陆海军入侵，但对于空中打击就无效了。

youdao

The land is useless growing crops; it's mainly swamp.

这块土地无法生长作物，他主要是沼泽地。

youdao

Soil on land where trees have been cut down quickly erodes away, rendering it useless, so more land soon has to be cleared.

BBC: Lemur

The land was virtually useless and lacked paved roads, plumbing and electricity.

CNN: 'Protest with a proposal'

Typically this meant plowing money into commodities, land, and other scarce if useless things (such as fine art), on the assumption that investment vehicles definitively limited in supply would hold their value in the context of dollar weakness.

FORBES: Now We Know Where the Inflation Went