After the completion of Széchenyi Chain Bridge (1849) it was urgent to drill a tunnel through the neighbouring Buda Castle Hill with the aim of making the traffic easier. At the outset, the imperial Habsburg court did not want to allow a tunnel in Castle Hill, because it was designed under the Royal Palace. However, the tenacious leaders of the tunnel company ”assaulted” Emperor Francis Joseph with their proposals regularly. In the end, the situation became fairly awkward for the ruler so he permitted the project, moreover, he sent 80 tons of explosives for the works. The designer of the 350 meters long tunnel was the popular contractor of the former bridge-construction, namely, Adam Clark from Victorian Scotland. The style of the tunnel was Hellenistic Neo-Renaissance so it was influenced by the antique Greek architecture but it had some Italian touches too. Adam Clark became a Hungarian citizen, he did not accept the offered Hungarian nobility though (because he was proud of his Scottish nobility). He fell in love with the Hungarian Mária Áldásy. They first met in the former Buda Castle Theatre, later they married. He is not a really known architect in Scotland but is considered almost a national hero in Hungary. The place between the bridge and the tunnel is known as Clark Ádám tér (Adam Clark Square) today. An office and a flat was also constructed in the tunnel for the former toll-collectors. Today the inspector of the bridge works there.