Bich Dong — "Green Pearl Grotto" — is a pagoda complex built into and onto a limestone cliff about 2 kilometres from the Tam Coc boat dock. Founded in 1428 under the Le dynasty, it comprises three separate pagoda buildings: the Lower (Ha), Middle (Trung), and Upper (Thuong) temples, each at a higher elevation on the cliff face.
The Lower Pagoda is in a cave at the cliff's base, cool and incense-scented. Climbing further takes you through a narrow passage into the Middle Pagoda, and another steep path reaches the Upper Pagoda at the summit, with panoramic views over the rice fields and karst below. The whole climb takes 20–30 minutes and requires some agility on the steeper sections.
Easily combined with Tam Coc as a half-day outing. The pagoda sees fewer visitors than the boat trip and rewards those who make the climb.