If you want to be as safe as possible:

• Take the option Bus instead of Metro, it allows you to wait outside and you can always decide to leave it or not board it if it’s too crowded.
• Alternately, rent or use a bike to reach the beginning of the walk, and change its itinerary at one point to make it a loop tour.
• Skip the visits inside or make a reservation if it’s open.
• Keep your distances and wear a mask.
• Be prepared to forget restrooms and restaurants. If not, having hand sanitizer will be useful.
• Walk early in the morning, late in the evening and/or during an off-rush hour weekday to have more space for you.

The time indicated for the walks will be reduced: they become trails that still allow you to discover the city but you will have to do them again later to be able to visit in detail as described.

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