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The long line
The long line is often used as a counterexample in topology.
It can be defined as lex ℝ (Ico (0 : ℝ) 1) which is already equipped with its order thanks to order.lexicographic and a topology thanks to preorder.topology.
Relatingly, one could also study the long ray, the one-point compactification of the long line, the extended long line... Those should all essentially be the same.