A large part of the district area is taken up by the campus of Chulalongkorn University and the green expanses of Lumphini Park and the Royal Bangkok Sports Club.

By the turn of the 20th–21st centuries, the district had become known as the modern-day city centre, home to the prominent shopping areas of Siam and Ratchaprasong.

When King Rama I established Bangkok as his capital in 1782, he had canals dug including Khlong Maha Nak, which extended eastward from the fortified city proper of Rattanakosin Island.

[2] Sometime before 1855, Mongkut had part of the royal fields south of the canal landscaped with ponds and waterways, which were planted with decorative lotuses, for leisurely visits.

[2] Windsor Palace had become vacant following Vajirunhis's death in 1895, and its grounds became the site of several successive educational institutions which became established as Chulalongkorn University in 1917 by King Vajiravudh (Rama VI, r. 1910–1925).

Gradually, Siam and Ratchaprasong supplanted the Wang Burapha area as Bangkok's centre of urban retail and youth culture.

[4][5] With the opening of the BTS Skytrain in 1999, the location of its central interchange at Siam station helped cement the neighbourhood's prominence as Bangkok's modern-day city centre.

Pathum Wan District occupies 8.369 square kilometres (3.231 sq mi) in Bangkok's Phra Nakhon side (east of the Chao Phraya River).

They are crossed by several roads running north–south: Rama VI–Charu Mueang, Banthat Thong, Phaya Thai, Henri Dunant, Ratchadamri, Chit Lom–Lang Suan, and Witthayu.

The Si Rat and Chaloem Maha Nakhon expressways run above Phra Ram VI–Charu Mueang and alongside the Maenam railway, respectively.

Along Rama I Road, Charoen Phon Intersection (where it crosses Banthat Thong) is marked by the nearby National Stadium, which stands on the former location of Windsor Palace.

Opposite the stadium complex to the north still lies part of the historic Ban Khrua community (though the main settlement is across Saen Sap Canal in Ratchathewi District).

It is a complex of traditional Thai houses near the Ban Khrua community from where the designer sourced the silk he popularized internationally.

It is a famous place of worship where locals and tourists come to make wishes, but also the site of Bangkok's deadliest terrorist attack in 2015.

The latter is named after the founder of the Red Cross, as the Thai Red Cross Society straddles its southern end, with the Queen Saovabha Memorial Institute (famous for its snake farm) on one side and King Chulalongkorn Memorial Hospital (one of the country's largest teaching hospitals, affiliated with the university) on the other.

Multiple bus lines run on the major streets, while both expressways have entrances and exits on Rama IV Road.

The MRT runs beneath Rama IV Road along the district's southern edge, with Hua Lamphong, Sam Yan, Si Lom, and Lumphini stations serving their respective neighbourhoods.