The Great Synagogue of Gibraltar, also known as Kahal Kadosh Sha'ar HaShamayim is situated behind a three-storey domestic looking façade with round headed windows and doorway at 49 Engineer Lane. The appearance is typical, with shuttered windows, although these lack the characteristic iron works balconies of Regency Gibraltar. The plain building is rendered and painted with stone quoins and surrounds. Some alterations were made in the centenary year of 1912, as the inscriptions in the stone window heads flanking the main door attests.1
The Great Synagogue was founded in 1724 and has been rebuilt several times in the ensuing 300 years of existence. The present building largely dates from 1812 and shares features in common with the parent Spanish & Portuguese synagogues of Amsterdam (1675) and Bevis Marks in London (1701). It is the oldest synagogue in continuous use in Gibraltar. The facade of the two-and-a-half-story, domestic-scale building features round-arched windows flanking a round-arched doorway. The interior features colourful tiles, wrought-iron balustrades, dark wooden furnishings, and marble floors.
The Great Synagogue owes its construction to the event leading from the expulsion of the Jews from Gibraltar in 1717 following pressure from Spain who argued that their presence contravened the terms of the Treaty of Utrecht. However, in that same year Spain broke its own promises and launched an expedition intended to recover Sardinia and Sicily which she had lost under those same terms. War ensured and supplies across the border was cut once more. The British had no alternative but to reopen trade talks with the Sultan of Morocco who refused to negotiate unless Jews and Moslems were allowed to settle in Gibraltar.
In 1724 Colonel Hargrave, Governor of Gibraltar presented a Jewish merchant, Isaac Netto, with a piece of land in Engineer Lane where he built a shed for use as a synagogue. Netto was the Governor’s secretary in all matters relating to Morocco so his influence was telling. Netto had been born in Leghorn and had been taken to London at a young age when his father became Chief Rabbi of the Spanish and Portuguese (Sephardi) Jews congregation in Bevis Marks in the City of London.2 The synagogue was an offshoot of the Sephardi synagogue in Amsterdam hence the similarities in features of the Sha’ar HaShamayim synagogue in Gibraltar.
Netto was therefore the founder and first religious leader of the Jewish community of Gibraltar. He organised the community along the same lines as that of Bevis Marks in London and gave it the same name of Kahal Kadosh Sha'ar HaShamayim which means "Holy Congregation Gate of Heaven." However, it became known as the Great Synagogue or Esnoga Grande locally. This makes the Great Synagogue in Gibraltar one of the oldest in the entire Peninsular.