Sequoia and Kings Canyon form a dramatic landscape of huge mountains, rugged foothills, deep canyons, vast caverns, and the world's largest trees in the southern Sierra Nevada east of the San Joaquin Valley. Lying side by side, the parks span elevations from 1,370 feet to 14,494 feet, creating wide seasonal and local weather differences. In summer, the sequoia groves have comfortable temperatures while the foothills are hot and dry, and snow remains on high mountain passes well into the season. In fall, some areas close or reduce their hours. Winter brings snow to the sequoia groves and rain to the foothills, with tire chains sometimes required. In spring, the foothills are well suited for hiking and snow begins to melt at higher elevations.