I went there recently on the Day of the Mask and there was music, food, performances by masked gigantes, etc. I went with a friend and her small child, who had a ball. Usually, it is a quieter place, very quiet, with some permanent exhibits, classes on folk culture and cooking, and lovely gardens. The exhibits are of traditional Costa Rican homes, furniture, etc.
Unless there is an event taking place, I would recommend it as a nice break from a busy trip. Think about binging a lunch and eating in the gardens.
It can be a little challenging to find. Taxis should be able to get you there from Heredia without any trouble. You can take the bus from Heredia toward Barva and get off by the Musmani bakery. I would suggest taking a cab from there unless you want to hike a mile or two and ask directions along the way. It is to the east of the Heredia-Barva highway in a district called Santa Lucia.
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