This was our 3rd dive for the day. We weren't sure we would find the lava tubes on our first outing, but we found them fairly easily. We snorkeled out about 1/3 of the way out of the bay and then dropped down - it was only about 10' for us - and then kept going out with a slight angle to the left. We went up and down several of the fingers of the lava tubes and finally found the ones with the arch swim through and the tunnel that ended with a chimney opening. We looked up and could see that the surge was pretty heavy at the time, so we opted not to go up and instead went back out the way we came in. We most likely would have had better vis had we come earlier in the day, but we wanted to do 2-step/Place of Refuge in the morning since we heard that place gets packed - glad we did because we had the 1st dive to ourselves. But about 4 Mile - it's a fun, short dive with not much sea life for us, though I know a shark can sometimes hide out in that tunnel. I read the info here and was planning to park on the street as the photos indicated but found the parking lot just to the north to be easier and closer to the 'sandy' entry (note, the sandy entry area is small but definitely doable). The rocks near the entry were large enough to set our BCDs/tanks and sit down to get everything fastened after getting our mask defogged. My buddy and I are both Intermediate Divers with 20-30 dives and enjoyed this dive as a variation from our other 2 shore dives at Place of Refuge.