Being a lone female I never felt unsafe in the Old City or La Ronda, even on a busy weekend evening (in fact with all that’s going on, that’s where you want to stroll around). My experience is that strangers are very kind in Quito, yes white females do stand out about, but mostly if people start chatting to you they are trying to help or just want to practice a little English. The apartment block has a big front gate and a very secluded feel to it meaning that I only ever felt comfortable and at home. I would have no qualms in recommending the Old City to solo-female travelers, in fact to not stay there would mean you really miss out on what feels different about Quito, compared with the more modern areas of La Mariscal in the North for example.
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