Stretching from the eastern suburbs of Johannesburg to the Mozambique border, the Eastern Transvaal included both the highveld and the Lowveld, which lies below the escarpment and benefits from a more swimming-friendly climate than the highveld, where the winters can be freezing cold.

The province is now known as  Mpumalanga and it no longer includes the cities of Boksburg, Benoni, and Germiston. Nelspruit is the provincial capital, although historically it was a small centre at the far eastern part of the province. Other towns to the north have been lost to the new Limpopo province.

Eastern Transvaal was once the home of the South African Amateur Swimming Union (SAASU). Issy Kramer, an attorney living in Boksburg, was the SAASU president. It was a powerhouse in South African water polo and a traditionally strong swimming province. In the 1960's many overseas champions like Ada Kok and Don Schollander swam at the Boksburg pool at SAASU hosted events. 

The old Eastern Transvaal ASA  is now known as Eastern Gauteng Aquatics.