Marhold has a decision to fix the tunnel.

^ Anyone holding Marrhold (province) can take the decision.

I feel like the devs should make it possible to repair the tunnel from the other direction as well

引用自 p0xus：

I feel like the devs should make it possible to repair the tunnel from the other direction as well

agree

You'll lose half your trade through Marhold once the tunnel is unblocked, would not recommend as a dwarf nation.

引用自 Diabeto：

You'll lose half your trade through Marhold once the tunnel is unblocked, would not recommend as a dwarf nation.

Not really as they trade from the province itself when you complete the project is mental