What is the cheapest way of travelling from Delft to Keukenhof gardens for a day return?
If you are thinking of the bulb fields, look at the official site:
Then bus 854 (or 50) from Leiden Centraal station to Keukenhofdreef Bus times on the official site:
Journey time is about 1.5 hours altogether.
The Netherlands public transport website in English is very helpful for specific timings:
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