Question: Both Ruijin and Pingliang are located near which type of land mass?
Context: Pingliang () is a prefecture-level city in eastern Gansu province, China, bordering Shaanxi province to the south and east and the Ningxia Hui Autonomous Region to the north.  Pingliang is well known for the nearby Kongtong Mountains, which are sacred to Taoism and location of the mythical meeting place of the Yellow Emperor and Guangchengzi, an immortal. Montana is a state located in the Western United States.  According to the 2010 United States Census, Montana is the 7th least populous state with inhabitants but the 4th largest by land area spanning 145545.80 sqmi of land.  Montana is divided into 56 counties and contains 129 incorporated municipalities consisting of cities and towns.  Montana's municipalities cover only % of the state's land mass but are home to % of its population.  The Montana Code 7-1-4124 gives municipal governments in Montana powers to enact ordinances, borrow money, and enact eminent domain among other legal powers. New Mexico is a state located in the Western United States.  According to the 2010 United States Census, New Mexico is the 15th least populous state with inhabitants but the 5th largest by land area spanning 121298.15 sqmi of land.  New Mexico is divided into 33 counties and contains 102 incorporated municipalities consisting of cities, towns, and villages.  New Mexico's incorporated municipalities cover only % of the state's land mass but are home to % of its population. Mississippi is a state located in the Southern United States.  According to the 2010 United States Census, Mississippi is the 32nd most populous state with inhabitants and the 31st largest by land area spanning 46923.27 sqmi of land.  Mississippi is divided into 82 counties and contains 299 incorporated municipalities consisting of cities, towns and villages.  Mississippi's municipalities cover only % of the state's land mass but are home to % of its population. A rail land bridge refers to the transport of containers by rail between ports on either side of a land mass, such as North America.  Jean-Paul Rodrigue defined a rail land bridge as having two characteristics: First, a single bill of lading issued by the freight forwarder that covers the entire journey, and second, the freight remains in the same container for the total transit.  One example of a rail land bridge is the Eurasian Land Bridge.  A transcontinental railroad can be a type of land bridge. Atmospheric methane is the methane present in Earth's atmosphere.  Atmospheric methane concentrations are of interest because it is one of the most potent greenhouse gases in Earth's atmosphere.  The 100-year global warming potential of methane is 28.  That is, over a 100-year period, it traps 28 times more heat per mass unit than carbon dioxide and 32 times the effect when accounting for aerosol interactions.  Global methane levels had risen from 722 parts per billion (ppb) in pre-industrial times to 1800 ppb by 2011, an increase by a factor of 2.5 and the highest value in at least 800,000 years.  Its concentration is higher in the Northern Hemisphere since most sources (both natural and human) are located on land and the Northern Hemisphere has more land mass.  The concentrations vary seasonally, with, for example, a minimum in the northern tropics during April−May mainly due to removal by the hydroxyl radical. Louisiana is a state located in the Southern United States.  According to the 2010 United States Census, Louisiana is the 25th most populous state with inhabitants and the 33rd largest by land area spanning 43203.90 sqmi of land.  Louisiana is divided into 64 parishes, which are equivalent to counties, and contains 308 incorporated municipalities consisting of four consolidated city-parishes, and 304 cities, towns, and villages.  Louisiana's municipalities cover only % of the state's land mass but are home to % of its population. Ruijin () is a county-level city of Ganzhou in the mountains bordering Fujian Province in south-eastern Jiangxi. South Korea is located in East Asia, on the southern half of the Korean Peninsula jutting out from the far east of the Asian land mass.  The only country with a land border to South Korea is North Korea, lying to the north with 238 km of border running along the Korean Demilitarized Zone.  South Korea is mostly surrounded by water and has 2,413 km of coast line along three seas.  To the west is the Yellow Sea, to the south is the East China Sea, and to the east is Ulleung-do and Liancourt Rocks in the (East Sea).  Geographically, South Korea's land mass is approximately 100,032 km2 .  290 km2 of South Korea are occupied by water.  The approximate coordinates are 37° North, 127° 30 East. The history of Kalahandi goes back to the primitive period where a well-civilized, urbanized, and cultured people inhabited this land mass around 2000 years ago.  The world's largest celt of Stone Age and the largest cemetery of the megalithic age have been discovered in Kalahandi.  This shows the region had a civilized culture since the pre-historic era.  Asurgarh near Narla in Kalahandi was one of the oldest metropolises in Odisha whereas the other one was Sisupalgarh near Bhubaneswar.  Some other historical forts in the region includes Budhigarh (ancient period), Amthagarh (ancient period), Belkhandi (ancient to medieval period) and Dadpur-Jajjaldeypur (medieval period).  This land was unconquered by the great Ashoka, who fought the great Kalinga War, as per Ashokan record.  In medieval period the region had played a prominent role to link South India, Eastern India and Central India region and witnessed the battle ground for Somavamsi, Chola, Kalachuris of Kalyani and Eastern Ganga dynasty.  Kalahandi region was the main route for Chola to attack Subarnapur.
Answer: Mountains