The approach to Hailongtun is a stone-paved path up Longyan Mountain from the base reception area, gaining roughly 400 metres of elevation over about 3 kilometres. The path was originally the fortress's supply road, engineered into the hillside with drainage channels cut into the stone — you can see them clearly in dry weather as parallel grooves on either side of the main track. The climb takes about an hour at a moderate pace, through mixed forest that thickens as you gain altitude.
The trail is well maintained and clearly marked, though it is genuinely steep in sections. Comfortable shoes are necessary; the stone surface is smooth in places and becomes slippery in wet weather. The descent uses the same path, which is harder on the knees than the climb. Most visitors allow two hours each way plus time at the top, making a comfortable day trip from Zunyi.