Niihama is enveloped by mountains to the south and east, hills to the west, and the Seto Inland Sea to the north.

Being surrounded by mountains, Niihama feels geographically isolated from its closest neighbors, Saijō to the west and Shikokuchūō to the east.

Niihama has a mayor-council form of government with a directly elected mayor and a unicameral city council of 26 members.

In terms of national politics, Niihama is part of Ehime 2nd district of the lower house of the Diet of Japan.

Even though the mine has since closed (its legacy is now preserved in a small museum and onsen attraction, Minetopia Besshi), Sumitomo remains a large presence in town.

Each of 50 neighborhoods in Niihama has its own Taiko float, which consists of an ornately decorated wooden center frame, covered in panels made of gold thread (three to a side).

Men and boys as young as 16 begin the festival before sunrise on its first day by carrying the floats to their local shrine for a blessing by shinto priests.

The most spectacular of these happens at Utsunomiya Jinja near Yamane Ground where several floats are carried up many steps at about 4am to a small shrine on the top of a hill.

It welcomes foreign visitors to participate in a Sunday morning zazen meditation session, or even to stay overnight.

Niihama is home to the national headquarters of the Otedama no Kai (お手玉の会, Traditional Japanese Juggling Association).

Niihama was home to the world's largest planetarium until the renovation of the Nagoya City Science Museum in March 2011.