Climbing up the Mediterranean Steps is probably one of my favourite activities to do in Gibraltar. I recommend avoiding doing it when it is wet, and probably when it is super hot too. Around May or September/October would be an idea time.
They are very not that popular with tourists as many choose to take a taxi/tour up the Rock instead. Locals use them for training, and you sometimes see people running up and down to get a workout.
They are, without doubt, a must do activity if you are in Gibraltar for more than one day. Leave about half a day free for this. Whilst the actual climb can take you under 2 hours, the views are so beautiful that you want time to actually look around and enjoy. I would also recommend then walking across the Nature Reserve too, you can start at the Med Steps, then when you reach the top, make your way to St Michael's Cave, followed by the Apes Den and then the The Great Siege Tunnels.
No doubt you do have to be relatively fit to do this. Wear shoes with a good grip, take lots of water and snacks with you (especially if you plan on spending all day exploring the Upper Rock).
It is a great sense of achievement to reach the top, and it gives you an inkling of why Gibraltarians are so proud of their Rock, and love it like nothing else on earth!
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