Here's what it looks like inside NASA's Human Exploration Research Analog.

The exterior of the HERA
Two test subjects read in cramped sleeping quarters
The lower level and ladder leading to upstairs of the HERA
The upper level of the HERA
HERA's gym
Ulyana Horodyskyj stands outside the HERA "Hygiene Module"
Horodyskyj practices landing on an asteroid from inside the HERA
The four members of Mission XII celebrate after the mission is over
Horodyskyj back home in Boulder wearing her flight suit