Both cities have pluses and minuses and are equally dark on sidestreets after nightfall and you should not walk alone or with other foreigners in either in unlighted areas after dark. Nicaragua is the second poorest country in the hemisphere after all and while relatively safe compared to CA countries to the north, incidents happen. By reputation, Escuela Horizonte in Esteli is the best Spanish language school in the North, if that is a significant factor in your decision process. Check out their website, which gives some info on side day trips out from Esteli as well. Unless one is very interested in the revolutionary events of 1978-1985 or some of the best cigar making factories in the world, there is not much to see in town. Esteli has lost what rustic charm it had decades ago, but the daytrip of hiking with a group along the ridgeline of el Tisey is some of most spectacular Nicaraguan scenery, visit the stone carvings nearby and perhaps visit la Cascada, but that is more problematic in my opinion. Miraflor is a great concept, but can be hit or miss as a great visiting experience and in the past there has been reported disorganization in coordinating a trip there and back. Roadbed to Miraflor can be pretty rough. I am still stuck on Hotel La Selva Negra as the best concentrated cloud forest experience in Nicaragua, but, as I have stated in other postings, some friends of mine rave of it being the highlight of their trip to Nicaragua (love listening to the howler monkeys while at breakfast), others checkout after one night miserable from the cold and high humidity (Do the ridgeline hike there, but again not alone.) Check out their website. Whatever the humidity or temperature, la Selva Negra is the most comfortable lodging in the North, granted this is all relative. If cultural interaction and some language training are your top goals (I can't comment on the volunteering thing), do the week of Spanish in Esteli, stay in a home away from yanquis to force yourself into the local scene, do some afternoon side trips, Spend a morning or afternoon in Matagalpa on the way to Selva Negra, stay a night there, hike the ridge the next day, stay the night again following day bus into Jinotega and then head back south or take the rough, "short cut" from San Isidro over to Leon. If you would like more specific activities/ideas on Esteli and surrounding area, PM me. December through early February is the most pleasant time of year to visit the northern highlands.
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