For the international understanding on soil classification systems, three soil profiles (Pedons 1, 2, and 3) located in the Tokachi Plain, Hokkaido, Japan, were selected to explore in the field excursion tour on the first day of the 7^th International Soil Classification Congress (June 6th, 2024). Pedons 1, 2, and 3 were located in middle terrace, lowland, and middle terrace, respectively. The present study aimed to record the pedon data in detail and clarify the differences among Japanese and international soil classification systems for the improvement. The three Pedons were classified according to Soil Classification System of Japan (2017), US Soil Taxonomy (Keys to Soil Taxonomy, 13^th edition, 2022), World Reference Base for Soil Resources (4^th edition, 2022), as follows:

Pedon 1: Humic Allophanic Andosol (Soil Classification System of Japan)
Medial, amorphic, frigid Thaptic Hapludand (US Soil Taxonomy)
Oligoeutric Vitric Silandic Andosol (Loamic, Humic, Panpaic) (WRB)

Pedon 2: Aquic Brown Fluvic soil (Soil Classification System of Japan for preliminary survey site)
Haplic Brown Fluvic soil (Soil Classification System of Japan for field excursion site)
Mixed, frigid Aquic Udipsamment (US Soil Taxonomy for preliminary survey site)
Sandy, mixed, frigid Oxyaquic Hapludoll (US Soil Taxonomy for field excursion site)
Eutric Endogleyic Endofluvic Regosol (Epiloamic, Katoarenic, Humic) (WRB for preliminary survey site)
Luvic Endofluvic Phaeozem (Anoloamic, Humic, Bathygleyic) (WRB for field excursion site)

Pedon 3: Haplic Wet Andosol (Soil Classification System of Japan)
Medial over loamy, ferrihydritic, superactive, frigid Typic Melanaquand (US Soil Taxonomy)
Eutric Anthromollic Vitric Andic Gleysol (Pantoloamic, Abruptic, Hyperhumic, Mulmic, Amphiraptic) (WRB)

Pedon 1 was consistently classified as an Andosol/Andisol in the three classification systems. However, Pedons 2 and 3 were classified differently depending on the classification systems. The major differences would be derived from the identification of diagnostic properties and priority of the major soil groups in their key out systems. Although further improvement has not been discussed in the present study, it is valuable to recognize the differences among the soil classification systems. The soil profile data described here would contribute to further discussion for the improvement of the soil classification systems.

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