Lord Snow here recommends
sealing the TUNNEL,
Game of Thrones Season 4, Episode 7
Into the TUNNEL and out the other side.
Game of Thrones Season 1, Episode 3
We should have sealed the TUNNEL
while we had the chance,
Game of Thrones Season 4, Episode 9
They are working with heavy machinery.
Indeed, they’re building a TUNNEL.
Money Heist Season 1, Episode 11
So far they’ve confirmed
that they’re building a TUNNEL.
Money Heist Season 1, Episode 13