▁from ▁which ▁sight - see ing ▁fl ights ▁operated . ▁ 1 9 5 5 : ▁The ▁first ▁central ▁terminal ▁building ▁was ▁named ▁Building ▁ 1 ▁Europa . ▁ 1 9 5 6 : ▁The ▁second ▁central ▁terminal ▁building ▁( an ▁extension ▁on ▁Building ▁ 1 ) ▁was ▁named ▁Building ▁ 2 ▁Britann ic . ▁ 1 9 5 7 : ▁The ▁West ▁London ▁Air ▁Terminal , ▁a ▁check - in ▁facility ▁for ▁British ▁European ▁Air ways , ▁began ▁operations . ▁▁ 1 9 6 0 s ▁▁▁ 1 9 6 1 : ▁Run way ▁lengths : ▁Run way ▁ 1 0 L ▁ 9 3 1 3   ft , ▁ 1 0 R ▁had ▁been ▁extended ▁west ▁to ▁ 1 1 0 0 0   ft , ▁ 5 L ▁ 6 2 5 5   ft , ▁ 5 R ▁ 7 7 3 4   ft , ▁ 1 5 R ▁ 7 5 6 0   ft , ▁ 1 5 L ▁not ▁in ▁use . ▁▁ 1 3 ▁November ▁ 1 9 6 1 : ▁Building ▁ 3 , ▁the ▁Ocean ic ▁building ▁( ren amed ▁as ▁Terminal   3 ▁in ▁ 1 9 6 8 ) ▁opened ▁to ▁handle ▁long - ha ul ▁flight ▁depart ures . ▁The ▁roof ▁gard ens ▁on ▁the ▁Queen ' s ▁Building ▁and ▁the ▁Europa ▁Terminal ▁remained ▁popular . ▁ 1 9 6 4 : ▁The ▁document ary ▁City ▁of ▁the ▁Air ▁is ▁fil med ▁at ▁He ath row . ▁The