While exploring with a map selected in the hotbar causes the realm to crash in certain areas. All players on the server are also kicked, and no one is able to rejoin the server for about 5 minutes with error "Unable to connect to world". When traveling to area without a map, everything works fine.

*UPDATE* This issue only occurs when a) you venture into the area in which it is occuring; AND b) the map is selected in the hotbar. If you select the map while within the area of the problem, the server will crash. Again, the entire realm crashes; I know this because it kicks all players off, not just the person with the map. I have recreated this problem with two different computers on two different LAN's, and two different realms (one is survival and the other is creative), with the other players either on the same LAN or on seperate LAN's. It is easiest to recreate this issue on creative mode (because of flying), with a 1:16 map (I have had it on both 1:16 and 1:4). I have not been able to figure out why these areas cause a crash. I can go through both areas without a map just fine. Neither one is the same biome (one is a hilly beach area and the other is a swamp).

Seed:
-635438843

Coordinates:
588, 109, -1633
309, 79, -372