Spring (April to June) and autumn (September to November) are the best times, with warm days, cool evenings and the Sierra Nevada often still snow-capped behind the Alhambra. July and August are hot and busy, though the altitude keeps nights bearable, while winter is cold and quieter, with skiing up in the nearby Sierra Nevada.
Granada is built on hills, and the Albaicin and Sacromonte are a maze of steep, cobbled and stepped lanes. Wear sturdy shoes, take care on slippery stones after rain, and use a bus or taxi for the climbs if you tire or the day is hot.
Granada is generally safe, but pickpocketing and bag-snatching happen in the crowds at the Alhambra, San Nicolas viewpoint and busy tapas streets. Keep your bag closed and in front, watch your phone, and stay alert around anyone who crowds or distracts you.
At around 700 metres and beneath high mountains, Granada has strong summer sun and genuinely cold winters. Carry water and sun protection for open sites like the Alhambra in summer, and pack warm layers in winter, when evenings and the higher quarters get chilly.