According to Maha PariNibbana Sutta, The Buddha himself addressed Ananada Thero and made a statement as follows.

“ Chaththaari Maani Ananda
Saddhassa kulapuththassa
Dassaneeyaani,sanvejaneeyaani thaanaani
Katamaani chaththaari 

 Iddha Thathaagatho jaathothi Ananada
Saddhassa kulapuththassa
Dassaneeyaani,sanvejaneeyaani thaanaani
Iddha Thathaagatho anuthththaro samma sambodhi

Abhisambuddhothi Ananda
Saddhassa kulapuththassa
Dassaneeyaanan,sanvejaneeyaanan thaanan

 Iddha Thathaagatho anuthththaran Dhammachakkan
Pavaththitanthi Ananda
Saddhassa kulapuththassa
Dassaneeyaanan,sanvejaneeyaanan thaanan

 Iddha Thathaagatho anupaadhisesaaya,nibbhanadhaathuya
Parinibbuthoothi Ananda, sadhassa kulapuththassa                      Dassaneeyaanan,sanvejaneeyaanan thaanan ”

The Gautama Buddha himself had addressed Ananada Thero and said that “Ananada, ones who seek Nibbana, ones who are on the path of Dhamma, Kula Puthras who are devoted & want to be Dassanena Sampanna, ones who want to be satisfied in thoughts and to achieve Samma Ditthi – to attend in to the Sothapaththi[1] stage through the path of Sothapaththi – there are four places to visit & to pay the homage which will undoubtly assist and be assisted for the satisfaction in mind. Those four places are,

1. The birth place of prince Sidduhath.
   http://maps.google.com/maps?q=7.289069,80.760788&hl=en&t=h&z=16
2. The place where Gautama Buddha attended in to his supermandane Enlightenment.
   http://maps.google.com/maps?q=8.022746,80.735792&hl=en&t=h&z=16
3. The place where Gautama Buddha preached his very first sermon.
   http://maps.google.com/maps?q=8.567707,80.481675&hl=en&t=h&z=16
4. The place where Gautama Buddha attended to his parinibbana.
   http://maps.google.com/maps?q=6.633791,80.875546&hl=en&t=h&z=16

The devoted Kula Puthra is a special term used for the one who had listened to real Dhamma, directing his life in the correct path of Buddha Dhamma and entered in to the path of Sothapanna. Someone who had misled his life by rigid belief will not be having Saddha, the confidence. Since Buddha himself had preached and praised these four sacred places, it is necessary to discover these four places properly and understand the significance of them. The Buddha Shakthi [2] required to achieve supermundane fruitions (Maga Pala or Marga Pala[3]) in the Supermundane Paths (Maga) is centralized only in the association of these places. In the time that Buddha lived, there were many grate Arahants and these places were not that much important. It is because the devoted Kula Puthras could see the Buddha, listen to his voice, could experience Buddha spirit by themselves. But now a day, in order to get the real universal energy, these places should be correctly identified, visited and paid the due respects.

In order to establish a group of devoted Kula Puthras it is necessary to identify, disclose, preach the sublime Buddha Dhamma to the world. A genuine attempt to identify these places correctly and disclose them to the world would certainly be a great task to the mankind and that will be an aid for these noble ones to achieve the supermundane fruitions & attend in to Nirvana. It should also be mentioned that this truth is revealed in this manner and not having any idea to hurt anyone or to get some benefits enjoyed by them or to get anything else in return. In doing so, it is obvious to experience certain disapprovals. But, one day without being frightened, this whole truth should be disclosed to the world. The fear is a condition springs up in the ordinary mind. Today a majority of people who genuinely follows the sublime Buddha Dhamma is established in this Hela Deepa. This sublime truth is revealed in this manner to show and guide them on the correct path. In doing so, it should also be highlighted here that nothing of any recognition, propaganda, glory or benefits are expected.

A very long period like 1500 years, these four places with sacred Buddha Shakthi were covered and hidden by the effects of Dharmatha itself. It should be mentioned that alone with the disappearance of these places in time, many people lost the noble opportunity of attending in to Nibbana. As a result of the malformation and extinction of sacred Buddha Dhamma, not only these four key places, places like Devram Vihara where Buddha lived for twenty years, the city of Rajagaha, Veluwana Vihara and also many other sacred places which became so sacred due to Buddha’s presence with them, were disappeared in time. With the cessation of the supreme Buddha Dhamma and its new formation as a religious belief, Buddhism, made the devoted Kula Puthras rare and few. Ordinary followers who gave priority for religious beliefs and faiths were common and plenty. As a result, these sacred places were hidden off by the effect of the Dharmatha and in replacing them, some new places, models, came in to being and they got established. That is the nature of the Dharmatha. In a period where there are no any devoted Kulaputhras these sacred places will be disappeared and vanished by the effect of Dharmatha, it’s the nature of Dharmatha.

Disclosing the presence of these places and letting the devoted Kula Puthras to pay their homage to them is equally important as, in realizing Nibbana, it’s preaching the supreme Buddha Dhamma and attending into a Anusasana Praathihaaraya[4] through the preaching of “San”[5]. If someone wishes to achieve the spiritual purification through the true disclose of Patichchasamuppaada Dhamma[6]Dvathaa Dhamma[7],Thipariwatta[8] and Chathuraarya Sachcha Dhamma[9], and to be united with the universal energies released by the previous Buddhas, it’s a must to visit and pay homage to these places. Revealing this true knowledge only would be a great relief to the devoted Kula Puthras who genuinely attempt to experience ‘a fruit’ of the path of Nibbana in this life itself. Even today, these sacred places are well preserved to go and see them. The real intention or the expectation of revealing them is to giving a trouble free opportunity to go and pay the due respects for these places by the ones who are lucky enough to attend to Nirvana.

Due to some powerful Dharmatha, a long period of 1500 years, these sacred places were not known by the world. It should clearly be understood that these places were replaced with different structural models and people used to worship these new places. Since Buddha Shakthi or universal energy is not found in these structural models located outside Janbudveepa, any respective power helping the people to enable their spiritual purification cannot be experienced in these structural models. Hence, throughout the history, the pilgrims who went to these places in search of Buddha Shakthi, universal energy had lost the opportunity of experiencing that energy. Hence I decided to make this disclose now as its time to find all these places correctly and declare their presence to the world. This decision was driven purely by a genuine thought and I do not have any hidden agenda, not intending to get any benefits or to condemning or dishonoring anyone else. This should be considered only as a genuine course done towards the well being of the mankind.

Once its mentioned in a book of the most venerable Professor late Walpola Rahula once mentioned that some Bhikkus lived in Anuradhapura in Anuradhapura period, were not possessed with any spiritual real-understanding, yathaa bootha gnaana darashana, demonstrated by the sacred preachings of Buddha, but just lead an artificial life. This is the time to draw the attention of today’s educated Bhikkus and lay disciples on this statement again who consider Buddha Dhamma just as a faith. The ones in the Order, who lead an artificial life, had gone to its extreme end now and because of that now it’s the real time to reveal this truth.

(source : http://news.bbc.co.uk/2/hi/8767763.stm)