Along with Halong Bay, the Perfume Pagoda is a good day trip from Ha Noi. It will take about 2 and half hours to get to the site from Ha Noi.
Whilst called the Perfume Pagoda, it is in fact a vast collection of temples and caves spread over a large area – you will most likely be taken to see the main cave temple in Huong Tich Cave and the temples at the base of the mountain (where the cable car is).
The journey to the temple complex is by water; along the Day River. The boats are rowed by local townspeople (all women?) and seat about 6. The journey along the river will take about 40 minutes and is a delightful, calm way to arrive… at least it was when I went. This is a major pilgrimage destination for all Vietnamese, and they are well set up to handle vast numbers; there are hundreds of boats available to take pilgrims up the river, and there are extensive queueing ‘pens’ for when it’s busy. Peak time is Vietnamese New Year, but January to March can be busy; you might like to check before you go.
On arrival at the main temple quay, there are a few options: some temples, some dining places, and the route up to the main cave. The trail (about 2/ 3 km) can be walked or the temple reached by cable car, it is possible to cable car one way and walk back.
Apart from the physical stress of the walk, you should know that the entire route is lined with stalls selling pilgrimage items, food, souvenirs etc; if it is busy this could be quite difficult. Spare a thought for the stall holders: all their stock is brought up by foot…