How is geography structured and described in the novel Lost City Radio?

In Lost City Radio, the city is the epicenter of the country, surrounded by the mysterious and eerie jungle, which death and destruction have laid to waste. At the beginning of the novel, Victor is a refugee from the jungle, who the residents of his village, now renamed 1797, have sent to Norma in the city. They write her a letter, stating that they "have pooled our monies together, and sent him to the city" (page 5). They have done so because "we want a better life for Victor" (page 5). 
The city is where people go for hope, while the jungle is a mass of renamed villages whose histories have been erased. The towns in the jungle bear numbers related to their geography. Odd-numbered towns are near water, and those with high numbers are way up in the mountains. Alarcon writes, "Norma hated the numbers. Before, every town had a name; an unwieldy, millenarian name inherited from God-knows-which extinct people, names with hard consonants that sounded like stone grinding on stone" (page 5). The government's erasure of the old town names is a symbol, eerie in tone, of their attempt to eradicate the past. In the past, villages had solid foundations on maps; Alarcon compares the sound of the villages' old names, in a simile, to the sound of stone grinding on stone to convey how solid the old villages were. Now, given simply numbers, the towns seem ephemeral and without history.
The city is the center of the lost jungle, the place to which refugees come streaming for a better life. Norma's radio show, during which people call in looking for lost friends and family, is described in the following way: "And Norma listened, and then repeated the names in her mellifluous voice, and the board would light up with calls, lonely red lights, people longing to be found" (page 9). The red lights are symbolic of people from the jungle who stream and call into the city looking for hope.