Most of the major airlines offer flights from Mumbai and/or Delhi with usually one stop in between, i.e. Bangkok.
The best way to reach Phnom Penh is by air. The airport in the city enables you to land directly on the outskirts of the city, from where you can take a bus or taxi to get in. You can also take flights from some prominent cities in Cambodia to save your time while taking trips to multiple cities in the country.
You can travel to Phnom Penh from nearby cities like Siem Reap, Battambang, Sisophon, etc. by bus. There are two bus stations in the city: one near the Central Market, and another near the Night Market.
Ferries can be taken from Siem Reap as well as Mekong Delta (Vietnam) to reach Phnom Penh.
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