### Analysis of Busiest Airports by City: Atlanta and Incheon

#### Overview

The question regarding which city hosts the busiest airport in a country can vary significantly depending on the country in question. In the case of the United States and South Korea, the cities of Atlanta and Incheon are notable for their bustling airports, each serving as major aviation hubs within their respective countries. This document provides an extensive overview, comparing Hartsfield-Jackson Atlanta International Airport in Atlanta, Georgia, USA, with Incheon International Airport in Incheon, South Korea.

#### Hartsfield-Jackson Atlanta International Airport (ATL)

**Location and Development:**
Located in Atlanta, Georgia, Hartsfield-Jackson Atlanta International Airport holds the title of the busiest airport in the world by passenger numbers and the number of flights. The airport is strategically situated about 7 miles south of Atlanta's central business district. It covers an area of 4,700 acres and features five runways.

**Historical Context:**
The airport opened in 1926 and was originally named Candler Field after its location on the old Candler racetrack. As its services expanded, so did the infrastructure, and by the mid-20th century, it had grown into one of the major airports in the South of the United States. The airport was renamed in 1971 to honor former Mayors William B. Hartsfield and Maynard Jackson, who had played pivotal roles in the development of aviation in the city.

**Operation and Statistics:**
ATL leads in the operational statistics as the busiest airport by overall passenger numbers and flight operations. In 2019, the airport facilitated the transport of over 110 million passengers and conducted more than 900,000 flight operations. The airport serves as a primary hub for major airlines, including Delta Air Lines, which conducts a significant percentage of its operations from this airport.

**Facilities and Services:**
Hartsfield-Jackson is renowned for its efficiency and high capacity. It contains two terminals (Domestic and International) which are connected by several concourses housing about 192 gates. Facilities within the airport include numerous restaurants, retail outlets, lounges, and amenities designed to cater to a high volume of international and domestic travelers.

#### Incheon International Airport (ICN)

**Location and Development:**
Situated in Incheon, just west of Seoul, South Korea, Incheon International Airport is the largest airport in South Korea and one of the busiest airports in the world. It opened in 2001 to replace the older Gimpo International Airport, which now mainly serves domestic and shorter international flights. Covering an area of approximately 10,760 acres, Incheon Airport has continuously expanded its facilities to accommodate growing traffic.

**Historical Context:**
Incheon International Airport was constructed with the vision of becoming a major global aviation hub in Northeast Asia. Upon completion, it quickly gained a reputation for its highly efficient operations, state-of-the-art facilities, and exceptional services, winning numerous global awards for airport quality.

**Operation and Statistics:**
ICN has emerged as a key hub for international air traffic in Asia, serving as the primary gateway to South Korea. Pre-pandemic statistics from 2019 show that Incheon International Airport handled over 71 million passengers and more than 405,000 flights. The airport is a major hub for several airlines, including Korean Air and Asiana Airlines.

**Facilities and Services:**
Incheon International Airport features a wide array of passenger amenities and services that are among the best in the world. The airport has two main passenger terminals, connected by an automated people mover. The facilities include extensive duty-free shopping areas, a wide range of dining options, multiple lounges, cultural exhibits, and even a museum. Its efficiency in luggage handling and passenger processing times is well noted.

#### Conclusion

While Atlanta's Hartsfield-Jackson holds the title of the busiest by certain measures such as overall passenger count, Incheon International Airport is not far behind in terms of its international reputation and scale, particularly noted for its advanced facilities and excellent services. Both airports play critical roles in their respective regions and continue to expand their influence in the global aviation industry. The distinction between the busiest airports requires an understanding of different metrics such as passenger numbers, flight operations, international reach, and service quality, thus giving varying answers depending on the context of the query.