There are two ways to physically enter Bhutan: by air, or overland from India.
By air — Paro International Airport
Almost all international visitors arrive at Paro International Airport (PBH), one of the most dramatic approaches in commercial aviation — the descent winds between Himalayan ridgelines before landing in the Paro valley. Only two carriers currently operate the route: Druk Air (Bhutan's national carrier) and Bhutan Airlines, flying from hubs including Delhi, Kolkata, Bangkok, Kathmandu, Singapore and Dhaka. See our Bhutan flights guide for route detail.
Overland from India
Bhutan can also be entered by road from India, most commonly via Phuentsholing (bordering West Bengal) or Gelephu and Samdrup Jongkhar further east. This route is popular with Indian nationals (who need no visa) and travellers combining Bhutan with a trip through north-east India. Entry permits are still processed through your Bhutanese operator before you arrive at the border.
Getting around once you're there
Independent car rental isn't the norm — travel inside Bhutan is arranged through your tour operator, typically with a private vehicle and driver/guide included in your package. See transportation in Bhutan for more.
Planning tip
Because flights into Paro are limited (weather can also affect the mountain approach), it's worth booking your international flights and your Bhutan operator in parallel rather than one after the other — see how booking through Host Your Tour works.