The photo shows a manhole displayed on the website of "the ultimate manhole covers site." (The ultimate manhole covers site/Handout via Xinhua)

JERUSALEM, Jan. 23 (Xinhua) -- Eli Zvuluny from Tel Aviv has a unique habit. The 70-year-old documents manholes from around the world and catalogs them on a website that he operates.

While most people walk in the street and step on manholes without noticing them, Zvuluny was fascinated by their distinct features and shapes and decided to create an interface that maps those manholes that usually cover sewage infrastructure or other important underground facilities.

The photo shows a manhole displayed on the website of "the ultimate manhole covers site." (The ultimate manhole covers site/Handout via Xinhua)

Seven years into its operation, his website, titled "the ultimate manhole covers site," now records over 8,600 manholes from over 500 cities in 66 countries.

The software company owner has also developed a mobile phone application called "addmanhole," allowing users to upload pictures of manholes they have documented and add to the collection.

"The sky is the limit for me, there are a lot more countries I would like to receive pictures from," Zvuluny told Xinhua. "At first, people raised their eyebrows at my hobby, but now when my friends travel, they know they have to send me pictures of manholes."

"People get pretty psyched about it," he added.

The photo shows a manhole displayed on the website of "the ultimate manhole covers site." (The ultimate manhole covers site/Handout via Xinhua)

The website introduces eight different shapes of typical manholes, the materials they are made of, as well as their sizes and weights.

Each manhole has an entry on the website, detailing its unique characteristics. Some of them are in the shape of a bear, and some are designed by local artists and contain features that characterize the cities they are installed in. Many of them display small pieces of history or anecdotes about the city they lie in.

In cities like Seattle, the United States, there are manholes noting famous residents who were born in the city, such as guitarist Jimmy Hendrix.

The photo shows a manhole displayed on the website of "the ultimate manhole covers site." (The ultimate manhole covers site/Handout via Xinhua)

In Japan, many of its colorful manholes showcase the country's closeness and affinity to water and the ocean.

Already being kept busy by those manholes, he is now branching out to mapping other attractions, such as street monuments, heritage sites, unique house number signs and sculptures.