Mita
Mita
An bude layin farko na gaba daya na karkashin kasa a Landan ranar 10 ga Janairu, 1863. An gina shi a wani zurfin rami mai zurfi a cikin rami mai buɗewa. Ya haɗu da titin Bishops (Paddington) da Farringdon kuma yana da tsayin kilomita 6. Ƙarƙashin ƙasa na London ya girma cikin sauri kuma an ƙara ƙarin layuka. A shekara ta 1890 aka bude layin farko na wutar lantarki a duniya, layin dogo na City da South London ne ke sarrafa shi, amma a mafi yawan layukan har zuwa 1905 motocin motsa jiki suna jan karukan da ke bukatar amfani da injin niƙa da magudanan ruwa don isar da ramukan.
A halin yanzu akwai kusan tsarin metro 140 da ke aiki a duniya. Duk da haka, ba kawai manyan yankunan birni ne kawai ke yanke shawarar gina jirgin karkashin kasa ba. Babban birni mafi ƙanƙanta da aka gina jirgin ƙasa shine Serfaus a Ostiriya mai yawan jama'a 1200. Kauyen yana da tsayin mita 1429 sama da matakin teku, a kauyen akwai layin minimita guda daya mai tashoshi hudu, wanda aka fi amfani da shi don jigilar masu sikandire daga filin ajiye motoci da ke kofar shiga kauyen, a karkashin gangarawa. Abin sha'awa, hawan kyauta ne.
