Niteroi in Brazil has moderate safety conditions for solo female travelers. While the area is generally friendly and vibrant, it is always essential to keep in mind that certain neighborhoods can be less safe, especially late at night. It's best to stay in well-lit, populated areas, especially after dark, and always keep your belongings close to you. It is also advisable to learn some basic Portuguese phrases for easier communication. Using common sense, just like you would in any other city, can help ensure a safer journey in Niteroi.