Which is the only country with a coastline on both the Red Sea and the Persian Gulf?

Saudi Arabia, which is why it matters strategically out of proportion to any single pipeline - it can move oil to either side of the Arabian peninsula and therefore around either of the two chokepoints that constrain everyone else. The Strait of Hormuz at the mouth of the Gulf and Bab el-Mandeb at the bottom of the Red Sea are both narrow, both contested, and both bypassable by a country with ports on each.

The east-west pipeline across the country exists for exactly that reason, built in the 1980s during the Iran-Iraq war when tankers in the Gulf were being attacked. It has been used again during recent disruptions to Red Sea shipping, which pushed traffic around the Cape and made the alternative route worth its cost.

The Red Sea coast is also the site of the country's largest bet on what comes after oil. Neom, a planned development including a proposed linear city of mirrored walls 170 kilometres long, has been announced with figures in the hundreds of billions and repeatedly scaled back in reporting - it is either the most ambitious construction project ever attempted or an expensive illustration of what happens when a plan needs no one's approval.