There are / have been horse tramways in the following places in Belgium:
Knokke is a small city with (today) about 14.000 inhabitants (only 1500 inhabitants around the year 1900). It is situated in the province of West-Vlaanderen, at the most nort eastern side of the coastal line of Belgium, just near the border with the Netherlands.
From 1904-04-02 on there was a horse tram line from theat the M.Lippensplein (near the railway station) to the Van Bunnenplein (at the beach). It was in exploitation by the "Société anonyme du Tramway de Knocke sur Mer". The owner of this company was Louis Herreboudt, manager of a hotel in Knokke. The length of the line was 1,7 km.
In 1890 the steam tram reached Knokke, but that did not change the horse tram. But when in 1912 the line was elektrified, then the horse tram was replaced by an electric tram.
Unknown to me.
More information can be found: