The genius of Indian art, as Jawaharlal Nehru pointed out, also graced the Angkor Wat temple in Cambodia and the Borobudur in Java.

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Angkor Wat, a temple complex in Cambodia, and the Inca fortress of Machu Picchu in Peru (pictured above) are often cited as places of world-historical importance where a vast influx of tourists may be causing serious damage.

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After meeting up with the archeologist guide, visitors take a cycling tour (bikes are provided) through the temple complex and north toward the south gate of Angkor Thom, to check out the centerpiece of this ancient city, the Bayon temple.

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At ancient Angkor, for example, Phnom Bakheng temple is a prime spot for sunset viewing, which results in a lot of tourists congregating, climbing on ancient sculptures and platforms, and leaving empty water and beer bottles.

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