The Malta Railway opened in 1883, and never made much money. Its original metre-gauge line ran through Birkirkara to an inconvenient terminus, called Notabile, in a deep cutting outside the hill-town of Rabat.
The Malta Railway Company went bankrupt in 1890 and reopened two years later under the auspices of the Malta government which improved and in 1900 extended the line up to a station called Museum, nearer to the ancient capital city, Mdina.
In 1905 Malta Tramways Ltd opened its three routes to Birkirkara, Zebbug and Vittoriosa, two of which directly competed with the railway.
Both the railway and the tramways were British exports.
The olive green steam locomotives for the railway were built by Manning Wardle of Leeds, Black Hawthorne & Co of Gateshead and Beyer Peacock of Manchester.
The trams expired in 1929 and the railway closed two years later, both defeated by the relentless competition of Malta’s self-employed bus drivers.
The Valletta railway terminus was located next to the Royal Opera House: the tracks were underground and emerged on to a viaduct which crossed a ditch that formed part of the city fortifications and entered another tunnel. It then crossed another viaduct alongside the Porte des Bombes in Floriana.
The tunnels apparently remain in good condition, and have occasionally been opened to the public: https://www.timesofmalta.com/articles/view/20121022/local/Railway-tunnel-part-of-Malta-s-heritage.442073.
Both viaducts were originally timber, at the insistence of the military authorities who wanted to destroy them quickly if necessary in an emergency. Eventually they were rebuilt in stone and still exist. They’re easy to locate, thanks to a meticulously obsessive video: https://www.youtube.com/watch?v=_8OlMnpZvtQ. It helps to know what you’re looking for.
Several of the country station buildings survive. Hamrun is a scout headquarters; Birkirkara is a childcare centre; Museum station is a celebrated restaurant: [https://www.facebook.com/pg/stazzjonrestaurantrabat/photos/?tab=album&album_id=218770048333827].
Little else remains. The only surviving piece of railway rolling stock is a third-class carriage which has stood in the open for years at Birkirkara: https://web.archive.org/web/20170408171035/http://www.timesofmalta.com/articles/view/20170407/local/watch-maltas-last-surviving-train-carriage-chugs-toward-restoration.644585.
An intriguing hint that there may be more can be found in a news article about the reappearance of four reversible seats from one of Malta’s trams, suggesting that a tram body survives at St Thomas’ Bay: https://www.timesofmalta.com/articles/view/20170628/local/century-old-malta-tram-benches-found.651902
There are images of both the railway and the tramways at https://vassallohistory.wordpress.com/maltese-public-transport-since-1856-a-brief-history-of-the-public-transport-in-malta-the-omnibus-up-to-the-mid-1800s-the-only-means-of-human-transport-w.
It’s clear from an article in The Guardian that Valletta’s railway tunnels are only a tiny part of the fascinating underground beneath the city: https://www.theguardian.com/cities/2017/feb/20/malta-secret-tunnels-inside-newly-discovered-underworld-valletta.