the port was the stop ships had to take when entering the Bab-el-Mandeb; this was how cities like Mecca had received goods by ship. Yemen Airlines, the national airline of South Yemen, had its head office in Aden. On 15 May 1996, Yemen Airlines merged with Yemenia. During the early 20th century Aden was a notable centre of coffee production. Women processed coffee beans, grown in the Yemen highlands. Frankincense, wheat, barley, alfalfa, and millet was also produced and exported from Aden. The leaves and stalks of the alfalfa, millet and maize produced in Aden were generally used as fodder. As of 1920, Aden was also gathering salt from salt water. An Italian company called Agostino Burgarella Ajola and Company gathered and process the salt under the name Aden Salt Works. There was also a smaller company from India, called Abdullabhoy and Joomabhoy Lalji & Company that owned a salt production firm in Aden. Both companies exported the salt. Between 1916 and 1917, Aden produced over 120,000 tons of salt. Aden has also produced potash, which was generally exported to Mumbai. Aden produced jollyboats. Charcoal was produced as well, from acacia, and mainly in the interior of the region. Cigarettes were produced by Jewish and Greek populations in Aden. The tobacco used was imported from Egypt. Since the outbreak of the Yemeni Civil War spread to Aden in 2015, the city has been struck by constant protests over a range of issues, but especially concerning electricity generation. Aden's power grid is composed solely of diesel generators and is thus heavily dependent on imported fuel. The main power plant is al-Hasswa diesel power plant, which in June 2021 had only two turbines out of five running, producing up to 50 megawatts (MW) of power in a region where the deficit hovers around 300 MW. Nawfal al-Mojamal, the plant director, said "In its 35 years of existence, al-Hasswa station never had any kind of maintenance, except in 2016 ... when the two turbines were restored". Transportation Historically, Aden's harbour has been a major hub of transportation for the region. As of 1920, the harbour was in size. Passenger ships landed at Steamer Point now called Tawahi. During the British colonial period motor vehicles drove on the left, as in the United Kingdom. On 2 January 1977, Aden, along with the rest of South Yemen, changed to driving on the right, bringing it