The National Monument (Indonesia: Monumen Nasional, abbreviated Monas) is a 132 m (433ft) tower in the centre of Merdeka Square, Central Jakarta, symbolizing the fight for Indonesia. It is the nationa monument of the Republic of Indonesia, built to commemorate the struggle for Indonesian independence.

Construction began in 1961 under the direction of President Sukarno. Monas was opened to the public in 1975. It is topped by a flame covered with gold foil. The monument and the museum are open daily from 08.00 - 15.00 Western Indonesia Time throughout the week except for the last Monday of each month when the monument is closed.

 After the Indonesian government returned to Jakarta from Yogyakartain 1950 following the Dutch recognition of Indonesian independence. President Sukarno began to contemplate the construction of a national monument comparable to the Eiffel Tower on the square in front of the Presidential Palace. On 17 August 1954, a National Monument Committee was established and a design competition was held in 1955. This attracted 51 entries, but only one design, by Frederich Silaban, met any of the criteria determined by the committee, which included reflecting the character of Indonesia in a building capable of lasting for centuries. A repeat competition was held in 1960, but once again, none of the 136 entries met the criteria. The chairman of the jury team then asked Silaban to show his design to Sukarno. However, Sukarno did not like the design as he wanted the monument to be in the form of a linga and yoni. Silaban was asked to design such a monument, but his design was for a monument so large that it would have been unaffordable given the economic conditions at the time. Silaban refused to design a smaller monument, suggesting that construction be delayed until the Indonesian economy improved. Sukarno then asked the architect R.M. Soedarsono to continue with the design. Soedarsono incorporated the numbers 17, 8 and 45, representing the 17 August 1945 Proclamation of Indonesian Independence, in the dimensions of the monument.

 The construction of Monas proceeded in three stages. The first period, from 1961/1962–1964/1965 began with the official start of construction on 17 August 1961 with Sukarno ceremonially driving in the first concrete pile. A of total of 284 piles were used for the foundation block. A further 360 piles were driven in for the museum foundations, with work being completed in March 1962. The walls of the museum in the base were completed by October. Construction of the obelisk than commenced and was finished in August 1963. Work in the second stage, from 1966 to 1968 was delayed by shortages of funding and the aftermath of the 30 Septsmber Movement coup attempt. In the final phase, from 1969–1976, the dioramas for the historical museum were added. Problems remained once construction was complete, and work was needed to solve problems with water leaking into the museum. Monas was officially opened to the public on 12 July 1975. The location of Monas is known as Merdeka Square.

Taken from (for detail study): http://en.wikipedia.org/wiki/National_Monument_%28Indonesia%29p