The Mari El Republic is a federal subject of Russia (a republic). Its capital is the city of Yoshkar-Ola.
The republic is located in the eastern part of the East European Plain of Russia, along the Volga River. The swampy Mari Depression is located in the west of the republic. 57% of the republic's territory is covered by forests.
There are 476 rivers in the republic. Most of them are considered to be minor: 10–50 m wide and 0.5-1.4 m deep.
There are over two hundred lakes in the republic, most of them with an area less than 1 km² and depth of 1–3 m. Many lakes are located among swamps. Swamps cover large areas (10–70 km², up to 100 km²). Average depth of the swamps is .5-1.5 m (up to 3 m), but they are impassable in fall and spring due to flooding.
The territory of the republic is one of the more ecologically pure areas of the European part of Russia with numerous lakes, rivers, and forests. As a result, it is a popular destination for tourists looking to enjoy nature. One of the most popular destinations is Marii Chodra national park in the Ilet valley, where visitors can enjoy various activities such as boating, horseback riding, fishing, and mushrooming. Another is the Bolshaya Kokshaga National Reserve, where visitors can walk through virgin forests and observe local wildlife.