Prime Minister Narendra Modi, who arrived here on Saturday on a two - day bilateral visit to Saudi Arabia, visited the historic Masmak Fortress.
"A Fortress for unity: PM visits and tours the Masmak Fortress, an important place in the unification of Saudi Arabia, " external affairs ministry spokesman Vikas Swarup tweeted.
Located on Al Imam Turky Ibn Abdullah Ibn Muhammed street in Ad - Dira, Riyadh, the Masmak Fortress is one of the main attractions for visitors.
The word "masmak" means strong, thick and fortified and that is what this fortress is.
The castle was constructed during Mohammed bin Abdullah bin Rasheed's reign and came under King Abdulaziz's rule, when Riyadh was conquered in 1902. This was the turning point in King Abdulaziz's efforts to unify the country.
Earlier on Saturday, Modi was received at the King Khalid International Airport by Governor of Riyadh Prince Faisal Bin Bandar Al Saud.
This is the first prime ministerial visit from India to the oil - rich Gulf kingdom since the visit of then prime minister Manmohan Singh in 2010.
Modi is scheduled to meet with representatives of the nearly three million - strong expatriate Indian community later on Saturday.
He will be accorded a ceremonial welcome on Sunday afternoon at the Royal Court here by Saudi King Salman Bin Abdulaziz Al Saud.
King Salman will also host a lunch in honour of the visiting prime minister.
This will be followed by delegation - level talks and the signing of agreements.
During Modi's visit, ties between India and Saudi Arabia are expected to be further elevated from the current strategic partnership to a more broad - based one.
Modi will leave for India late Sunday afternoon.