But AU probably isn’t a good way to compare this.

Sun and the Solar System is 1,921.56 AU in diameter (google)

So in these Solar System Units Alpha Centauri is only ~140 SSU away. Still more than 25, but comparable, and we are not in a dense neighborhood, afair: https://astronomy.com/magazine/ask-astro/2006/01/how-close-c...

M15's center packs approximately 4 million stars per cubic parsec — that's more than 75 million times denser than the region around the Sun

But some galaxies pack stars even tighter. M32, one of the Andromeda Galaxy's satellites, has the highest measured stellar density of any nearby galaxy — around 20 million stars per cubic parsec in its core! Not even HST can resolve M32's core into individual stars. A typical stellar separation at this density works out to 0.008 light-year, or 500 AU — about 12 times the Sun-Pluto distance — between stars.

(500 AU being ~0.25 of our “SSU”, or 12 M32’s SSU)

We don't even need to travel to it. We can just wait a few billion years for it to come to us.

Of course, that raises the question of why some civilization with a billion year head start isn't here yet.

Wake me up when we get there.