Getting to Koh Phi Phi is fairly straight forward...

By Air
Krabi International Airport has regular flights from Bangkok and Koh Samui. Then it's just a short boat ride to Phi Phi from the main pier in Krabi Town.

By Train
The southern rail link, departing from Hualumpong Station in Bangkok:

.Bangkok
.Nakhon Pathom
.Ratchaburi
.Petchaburi
.Hua Hin
.Prachuap Kiri Khan
.Chumphon (for Koh Tao)
.Surat Thani (for Koh Samui, Koh Phangan, Krabi, Phuket)
.Trang
.Nakhon Si Thammarat
.Hat Yai (for Yala, Malaysia)

* There is no direct rail link to Krabi. You will need to catch a connecting bus from Surat Thani.

By Bus
All southern bus routes depart from the Southern Bus Terminal ("Sai Dai") in Bangkok and have direct routes to all major destinations, including Krabi.

---