Unfortunately when I was in the Elqui Valley a visit to the Mamalluca Observatory didn´t fit in well with our schedule as we had decided to stay only in Pisco Elqui further up the valley and not in Vicuña. For those with an extra night to stay in Vicuña it would seem worthwhile visiting the observatory as the area is well known for its clear skies.
The website below offers information on this attraction in English and Spanish. As I haven´t experienced this myself I recommend you look at the website for details.
On the road between La Serena and Vicuña, just before arriving in Vicuña at about Km 56 there is a small town called Gualliguaica and the Embalse Puclaro (Puclaro Dam). The Dam is worth a visit for its stunning views down the valley. The Embalse Puclaro is a place where water sports can be done also (water skiing, windsurfing etc.).
As Vicuña is the birthplace of Gabriela Mistral and that she won a Nobel Prize for Literature we thought it would be interesting to go to the museum built in her honor. The museum contained a number of her works and had information and artefacts from her life. The explanations for everything were only in Spanish.
Open Monday to Saturday from 10:00 to 13:00 and 15:00 to 18.00 and on Sundays and holidays from 10:00 to 13:00.
Entry for adults is $600 pesos and for children and senior citizens is $300 pesos.