The distance from Tauranga to Brisbane on the freighter ship I found out was 2654 km. My other travels from Lyttelton to Tauranga and traveling around Australia were about 8,000km. So from Lyttelton to Darwin with the traveling around Australia came to about 10,700km.
From Bali to Beijing, it was 9,000km. The Trans-Mongolian from Beijing to Moscow is 7865km.
From Moscow to Harwich I calculated that I covered about 4,100km.
10,700 + 9000 + 7865 + 4100
The end result? 31,665 kilometres. Since it's a rough calculation, let's call it 32,000 km.
I've just found a computer programme where I can draw lines on a map and measure distances that way so I'll give it a go and see if I can come up with a more accurate calculation.