Ascension is a rocky peak of purely volcanic origin (44 distinct craters - all "dormant", i.e. not "extinct") with its base just west of the mid-Atlantic ridge. Much of the island is covered by basalt lava flows and cinder cones. The last major volcanic eruption took place about 600 years ago. The highest point (Green Mountain) at some 2817 ft is covered with lush vegetation which, with each rainy season is increasingly spreading throughout the island. There is a small farm near the peak which used to produce vegetables and pork but has now sadly fell into disrepair. The climate on Ascension Island is subtropical.