7 km from Siem Reap
Once covered by the jungle and rarely visited, the temple area of Angkor is now part of the beaten track in Southeast Asia, but for a good reason. These magnificent temples were once the centre of the mighty Khmer kingdom (ninth century to the fifteenth century A.D.) and the main temple Angkor Wat is considered the world's largest religious complex. Remember to read up on Hindu mythology to get a chance to understand its outstanding bas-reliefs or just be impressed by the grand scale. Split your explore time equally between the big ones; Angkor Wat, Ta Prohm, and Bayon (picture) and the minor ones; Preah Khan, Neak Pean, and Preah Ko, which lack in scale but win in tranquillity. If your time permits, add some sites that are a drive out of the way, like Banteay Srei, Kbal Spean and Beng Mealea.
25 km northeast of Angkor Wat
Banteay Srei is a rather small temple compared to Angkor Wat and Bayon, but what a fine one it is. All the surfaces are elaborately decorated with some of the finest carvings from the Angkorian times. The name Banteay Srei means "citadel of women", probably referring to its small size and fine details. It was built in the 10th-century (about 200 years before Angkor Wat), not by one of the Angkor kings but by a counsellor to the king. It was dedicated to the Hindu god of Shiva, which also characterizes the carvings.
Luckily, Banteay Srei lies quite far from the main temple group, so even with all its splendor, it sees less tourists and can even be deserted at times, which only adds to its appeal.
Jungle temple of Beng Mealea
About 70 km from Siem Reap
Cambodia's treasure of ancient temples goes beyond the group at Angkor. The mystical temple of Beng Mealea is one of those. Built in the Angkorian period, 40 km from Angkor Wat on an ancient royal highway, it was among the biggest temples. Today, it is a magical ruin that has been hidden under the jungle carpet until recently. Giant serpent-like roots are slowly crushing the walls, while a web of smaller roots are holding the place together. You have to crawl over fine carved sandstone blocks, duck under fallen pillars, and hang in vines to get through the giant maze of closed courtyards, dark chambers and rising towers. Though there are boardwalks at some sections, it is a raw experience to explore this hidden jewel. This jungle temple makes Ta Prohm, the famous jungle temple at Angkor, look like a groomed little brother.
Phnom Banan, a tuk-tuk ride from Battambang
Prasat Banan is an Angkor temple ruin on top of the small mountain Phnom Banan (102 m) which rises abruptly above the otherwise flat countryside outside Battambang. It was built in the 11th century and consists of five classic Angkor towers. It is a tiny temple compared to Angkor Wat standards, but the location and serenity makes up for the small size - chances are you are going to have the whole place to yourself (beside the drink sellers). Danger signs remind you that the ruins are crumbling and judging by the leaning angle of some of the towers, they look like they could collapse at anytime. There are also some caves which can be explored - alone or with the help of one of the local kiddie guides.
River of a Thousand Lingas
About 50 km from Siem Reap
At the foot of Phnom Kulen lies a very different Angkorian site, namely Kbal Spean or in English "River of a Thousand Lingas". A linga is a phallic symbol of Hindu god Shiva. So the Angkor kings had the river bed of Kbal Spean river carved with "a thousand lingas" to make the water fertile for the rice fields - like a religious water filter. The lingas date back to the 11th and 12th centuries, but were only discovered in 1969, and then unreachable for another twenty years due to the fighting with Khmer Rouge. See the lingas on your way to Phnom Kulen.
Wat Ek Phnom
Another tuk-tuk ride out of Battambang
Another Angkor temple ruin outside Battambang (the other is Prasat Banan). Though the name contains the word Phnom, which means mountain in Khmer, the temple is located on flat ground. It was constructed during the 11th century and is today partly collapsed - but that just adds to the authenticity. Tall trees are keeping the ground in the shade, while a newer pagoda with a giant never-will-be-finished Buddha statue at the front makes it difficult to see the old temple from the dirt road. A trip out here goes through charming villages and flat farmland, which should be reason enough for visiting Wat Ek Phnom.
Wat Phu Champasak
46 km from Pakse and 10 km from Champasak town
An ancient Khmer temple complex built in Angkor style a bit earlier (11th century) than Angkor Wat in Cambodia (12th century). Bits and pieces were later added, so the similarities in design with its sister temple of Angkor are big, though it does not have any bas-reliefs. Wat Phu is built at the base of a hill, which due to its slight penis shape was considered a representation of Shiva, and therefore holy. Furthermore, a spring drips from the rock ceiling and, since the rock is Shiva's phallus, the water is therefore holy. So Wat Phu is a water temple in honour of Shiva and the only of its kind in the Angkor world. Additional fascinating things can be found on the site, like the crocodile rock and heaps of later added Buddha statues.
Angkor temple at Prasat Muang Tam
8 km from Phanom Rung Historical Park
Not far from the Phanom Rung temple lies another Angkor temple, Prasar Muang Tam, in the middle of a village. When you think you have seen all Angkor temple combinations, you will again be surprised by Prasat Muang Tam. After passing through the wall, you will encounter four giant pools filled with lotuses surrounding the inner complex where four red towers rise – originally, there were five towers but the center piece has collapsed. The temple is dedicated to the Hindu god of Shiva and due to reliefs and style of the nagas (the mythological serpent that snakes around the pools) it is belived that Muang Tam was built in the 11th century. If you have already been to Angkor Wat, you will realise that the ground plan is the same. Prasat Muang Tam is a very serene site and not many visitors come here so it is easy to get the place for yourself.
Angkor temples at Phanom Rung
Phanom Rung Historical Park
This is probably the best Angkor temple in Thailand. It is located on the top of an extinct volcano, was probably built during the 11th century, and has taken the Thais 17 years to restore. It is a beautiful complex consisting of a long naga-stairway leading up to a walled temple containing all the usual Angkor designs like towers, pavilions, pools and reliefs, that only make sense if you know your Hindu/Buddhist mythology. Luckily - and contrary to Angkor temples in Cambodia - the Thai have made an effort to put up discrete signs giving you a chance to understand the carvings. It is very groomed site with a manicured garden (unusual for Angkor temples in Cambodia), so just on that account Phanom Rung is a different Angkor ruin.