Before reaching the main building of the Istana, you will notice a cannon monument. This cannon is very popular among visitors for taking photos. Near to the cannon is an impressive fountain (see my tip on the fountain).
Once you enter the main gate of the Istana, you will immediately notice the huge outdoor compound and beautifully lawned open spaces of the compound leading to the main building. This is a breathe of fresh air from the urban skyscrapers of the Orchard Road area just outside the Istana. More photos are at the travelogue section of this VT page.
Just after you enter the main gate of the Istana along Orchard Road, there is a nice big pond with beautiful water lilies and other water plants (e.g. amazon lilies) to the left of the gate after walking on a big well lawned open space. This pond is very good for taking photos.
The walkways of the Istana are very comfortable for walking and are very wide, so there is no problem even on a crowded day. Anyway, the compound is so big and wide open that the crowd will spread itself nicely. Also, the walkways are lined with trees, plants and beautifully manicured lawn. The only thing here is do beware of the occasional vehicles using the walkways.
The gates of the Istana are very beautifully decorated, especially the main gate facing Orchard Road next to Plaza Singapura shopping centre. Do take note of the fine patterns on the gates as well as the national crest of Singapore at the main gate.
The main building of the Istana can be visited and the entrance fee is $$2 per person. No photography and video taping are allowed inside. Essentially, there is a fine display of many beautiful gifts received from various countries, historical items and furnitures, as well as the different rooms used for different official purposes e.g. entertaining foreign VIPs. This place is definitely worth a visit and usually quite crowded with visitors.
The Istana is full of history and dated back to the 1860s (see webpage below for more details). It has been the location where former and present President of Singapore welcome overseas VIPs to Singapore as well as hold major ceremonies, celebrations etc.