I can't speak highly enough of this volcano. The views of santiaguito, the surrounding landscape, and xela are incredible. Going at night has the added incentive of seeing the orange glow of lava and the sparkling lights of the city below. I would recommend going with Quetzaltrekkers, perhaps on their monthly full moon hike.
For those less athletic, rather than the summit you can go to the santiaguito mirador which is a very easy hike compared to the full Santa Maria climb.
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