Underground oasis in a Martian lava tube

Shane Powers (USA) & Linjie Wang (China) have created a design of an artificial underground oasis in a Martian lava tube for Marstopia international design contest held by Eleven Magazine. Their design named "Below Freezing" won the "honourable mention" award in the contest. Its main feature, besides utilizing natural lava tubes, is a vertical transportation system (surrounded by 3D-printed ice walls) to Mars's surface. Martian lava tubes could become very handy in creating large, radiation-protected spaces for future human colonists on Mars.