Explore a famous cave (e.g., Sung Sot) or stop at Ti Top Island for swimming and panoramic views; kayaking often available in calmer coves (kayak rentals may have extra fee).
Short morning excursion (cave or viewpoint) before returning to port and disembarking around late morning—confirm cruise schedule (many end ~10:30–12:00).
Scenic sampan boat through a series of caves and river valleys in the UNESCO-listed Trang An complex — boats operate from early morning to late afternoon.
Short but steep climb (several hundred steps) to a dramatic viewpoint over the Tam Coc valley — best late afternoon for light and fewer crowds (site open ~7:00–17:00).