Terrain
U+2668 HOT SPRINGS
U+2312 ARC looks like a hill
U+2248 ALMOST EQUAL TO rough water
Structures
U+2500 -- U+257F BOX DRAWING drawing walls and buildings
U+2302 HOUSE
U+265C BLACK CHESS ROOK could be a tower
U+271D CROSS or U+2671 EAST SYRIAC CROSS could represent a church or be a cross
Other cool things
U+2680 -- U+2685 DIE FACE roll them dice
U+231A WATCH
U+231B HOURGLASS
U+2744 SNOWFLAKE
U+2614 UMBRELLA WITH RAIN DROPS
U+2615 HOT BEVERAGE
U+263C WHITE SUN WITH RAYS
U+2388 HELM SYMBOL avast ye land lubbers
U+2639 WHITE FROWNING FACE
U+263A WHITE SMILING FACE have a nice day
U+2690 WHITE FLAG
U+2691 BLACK FLAG
U+2692 HAMMER AND PICK
U+2693 ANCHOR harbor (on maps)
U+2694 CROSSED SWORDS battleground (on maps)
U+2695 STAFF OF AESCULAPIUS medicine
U+2696 SCALES jurisprudence
U+2697 ALEMBIC chemistry
U+2698 FLOWER
U+2699 GEAR technology, tools
U+269A STAFF OF HERMES commerce