What tee-based development happened in 1870?

Question

Golf has evolved over the years, but what development occurred in 1870 that is still part of the game today?

Answer 1

It sounds like a very simple thing, but 1870 is the approximate date of the introduction of separate teeing grounds. Before then, players had teed off for the next hole from the green of the preceding hole - not a move that would be especially popular with today's grounds keepers.