Saguaro 'family' and Milky Way, Saguaro National Park, Arizona, USA

Prickly giants

These giant saguaro cactuses only grow in the Sonoran Desert, stretching across parts of northern Mexico and the US states of Arizona and California. Slow-growing, it takes them 35 years before they start to produce flowers and can take between 50 and 100 years to grow branches – if they do at all. These prickly behemoths eventually tower up to 52ft (16m) over Saguaro National Park in Arizona, although the tallest ever measured was 78ft (24m). And they have staying power, usually living for between 150 and 200 years. The park was established on 14 October 1994 to protect giant saguaros like these. Just don't be tempted to climb one. A closer look at that celestial display isn't worth getting jabbed by their 8cm saguaro spines.