Harry Potter and the Half Blood Prince
Crest Locations

Introduction
On Hogwarts, there are a total of 150 crests to collect.
25 of those you get by collecting mini-crests.
You need a total of 25000 mini crests.
You can get these crests by casting Depulso on glowing objects.
The other 125 crests are hidden on Hogwarts and for you to find.
I am trying my best to describe the locations.

There are several ways to collect crests:
#       Some are lying on the ground. Just walk over them.
#       Some are out of reach but visible.
       Cast Wingardium Leviosa.
#       Some are on a plateau on the wall or are hold by a statue.
       Cast Wingardium Leviosa on a nearby object,
       like a bench or flowerpot, and knock them of there position.
#       Some lay broken  on the floor. Cast Reparo.
#       Some are stuck in or behind a plant.
       Cast Incendio to set them free.
#       Some are behind a gate. Cast Depulso to break them.
       Then Wingardium Leviosa to get them through the gate.
       Then Reparo to fix them.
#       Some are behind a spider web.
       Cast Incendio on the web and Wingardium Leviosa on the crest.

There are also lion statues who are holding a crest. You have to
complete a sort of mini quest to set it free. This can be a duel or
making a potion. There are 10 of these lion statues to find.

There are also specific banners hanging from the ceiling. You have to
hit these banners, a couple on a row, to  release the crest.
There are 5 of these banner runs.

Then there are firework boxes. Set them of with Incedio to release
the crest. Then cast Reparo to fix it. There are 5 firework boxes to find.

Walk  with Luna
1-3     On the way to the castle with Luna, you come across these.
4       Up the steps past Hagrid’s hut to the left near the trees.

Gryffindor common room
5       On the wall above the fireplace.
6       On the left wall above the archway to the dormitory’s.

Gryffindor boys dormitory
7       On the left between two beds.

Grand staircase
8       From the Gryffindor tower go straight ahead, then left.
       Then look to the left, it’s on the wall.
9       Go further down the stairs to the left. You walk over it, can’t miss.
10      At the bottom under the stairs.
11      From the entrance hall go down, left, right, right, it’s on the left.

Entrance courtyard
12-13   On the left and right of the entrance doors on the wall
14      Go to the stairs leading to the boathouse. It’s on the right
       on a ledge under the window.
15      There is a lion statue in the left corner.
16      Go out of the courtyard towards the viaduct. To the left
       in the corner lies a broken crest.
17      Go towards the paved courtyard. It’s on the left wall, behind a plant.

Viaduct
18      Just outside the viaduct, when facing the bridge it’s on the left
       near the steps.
19      On the inside above the big doors.
20      Behind the pig statue
21      Above the archway to potions dungeon.
22      Go up the stairs, through the doors, it’s on the left
       behind a spider web.
23      Continue down the hall, it’s above the doors.
24      There is a banner run here.
25      Go through the doors and then right. It’s above the doors
       leading to the transfiguration courtyard.

Potions dungeon
26      Coming from the shortcut portrait, it’s on the left wall,
       behind a spider web.
27      Next to the previous crest is a small room. There is a crest behind the gate.
28      Out of this room to the left. Go down some steps to the right.
29      Go back up the steps and then right under the arches.
       Turn around and look up, is on the left.

Fifth floor
30      Coming from the grand staircase, go down the steps and through the door.
       Turn around, it’s above the door.

Clock tower
31      Coming from the fifth floor straight ahead, behind the bells,
       on a wooden beam.
32      Go to the left, it’s next to the stairs.
33      Go all the way down the stairs. There is a lion statue in the corner.
34      There is a crest on the back of the clock pendulum.

Clock tower courtyard
35      When facing the clock tower it’s to the left, through the archway.
36      In the right corner near the tree lies a broken crest.
37      On the wall in the left corner behind a plant.
38      there is a fireworks box in the middle of the courtyard.

Hospital wing corridor
39      Coming from the clock tower there is a lion statue on the left.
40      At the end on the wall to the left.

Covered bridge
41      Coming from the clock tower courtyard towards the stone circle
       there is a crest halfway down the bridge.

Hagrid’s hut
42      On the roof of Hagrid’s hut.
43      To the left on a stone in a plant.
44      At the end to the left.
45      There is also a lion statue at the end.

Stone circle
46      Looking at the covered bridge, it’s above the doorway.
47      To the left of the bridge, in a plant.
48      Towards the owlery on a stone to the left.
49      A little further, towards the cave, is a fireworks box.

Owlery
50      On the outside wall, left of the entrance.
51      As you enter, it’s under the stairs.
52      Go up the stairs, to the first floor. It’s under the stairs.
53      Go up the stairs, it’s behind the gate.

Quidditch cave
54      On the wall above the entrance to the cave.
55      On the path next to the pond, you can’t miss it.
56      Go around the pond, on the wall straight ahaid, near some stalagmites.

Quidditch tower
57      Go down the stairs and look through the big arch shaped windows to
       the opposite tower. There is a crest on the wall.
58      Exit the tower and go left up the stairs. There is a crest
       behind the bench in the corner.

Quidditch locker room
59      In the middle of the room, on a pedestal.

Training grounds
60      Coming from the quidditch locker room go up the stairs and then left,
       it’s in a plant.
61      Go around the fenced area, it’s on the wall left of the tower with
       huffelpuff flags.
62      Follow the wall to the right, there is another one on the
       wall behind a plant.
63      Continue along the wall. Up the small steps.
64      Facing the herbology entrance, it’s on the left behind the gate.
65      Turn around, it’s in the middle on a stone.
66      On the right of the herbology entrance behind a gate.
67      From previous crest, look to the right on the wall, it’s
       above the alcove with the flowerpot.
68      Around the corner on the left side in an alcove behind a spiderweb.
69      Continue down the path, you’ll come across a lion statue.
70      there is a firework box near the fenced area.

Herbology
71      From the training grounds, through the small room, take the greenhouse
       to the right, it’s left in some bushes.
72      Exit this greenhouse, look up to the left wall, above the entrance.
73      Turn around, at the end between the greenhouse, on the ground
       lies a broken crest.
74      In the other greenhouse, all the way to the end to the left.

Herbology corridor
75      Coming from herbology, immediately to the right in a pot.
76      There is a banner run here.
77      In the corner is a lion statue.
78      Around the corner on a bench.
79      Go right up the stairs, it’s to the left on the wall.

Library corridor
80      Coming from the herbology corridor, it’s around the first
       corner on the left wall.
81      At the end near a desk, lies a broken crest on the floor.

Charms classroom
82      On the right wall.
83      On the left at the end of the table.

Library
84      There is a lion statue in the left corner.
85      All the way at the back, it’s behind the middle gate.
86      Turn around and go left. It’s between two bookcases to the left.

Paved courtyard
87      Coming from the grand staircase, go through the door then turn around,
       it’s above the door on the wall.
88      Go up the stairs and follow the path, at the end go left,
       at the end is a crest.
89      Go up the stairs, there is a firework box here.
90      Continue, at the end is a crest on the wall behind a plant.
91      In the small tunnel towards the boathouse is a crest on the left wall.

Dungeon corridor
*At the end of this corridor is a stairs to the 6th an 7th floor*
92      Coming from the potions dungeon,  it’s on the left near the metal fence.
93      A bit further on the left wall.
94      A bit up the stairs at the end of the corridor.
95      Halfway up the stairs is a crest hold by a statue.

First floor
96      Coming from the grand staircase, follow the corridor, go left,
       continue through the double doors, turn around, it’s above the doors.

Third floor
97      Coming from the grand staircase, go down the steps and into the corridor.
       Halfway this corridor stand a statue on the left holding a crest.
98      Continue down the hallway, down the stairs,
       it’s on the left behind a gate.

Suspension bridge
99      Coming from the 3rd floor, it’s above the opposite doors on the wall.
100     There is a lion statue on this bridge.

Boathouse
101     Coming from the entrance courtyard, It’s on the stairs to
       the boathouse, near the end.
102     It’s high on the wall of the boathouse, you can see it when
       you’re coming down the stairs.
103     It’s on the wall above the doorway.
104     When going toward the paved courtyard, it’s hidden in
       the bushes to the left.
105     Proceed towards the paved courtyard, it’s on the rock wall on
       the right, behind a plant.
106     There is a firework box on the path between the boathouse
       and the paved courtyard.

Sixth floor
107     There is a banner run on this floor.

Seventh floor
108     Coming from the grand staircase, follow the corridor,
       it’s in a small alcove on the left.
109     Continue forward, it’s on the wall above the door.
110     Turn around, go left, left again, it’s to the right on the wall.
111     There is a banner run on this floor.

Stone bridge
112     Coming from the viaduct corridor, it’s above the doors you entered from.
113     It’s on the side next to the opposite doors.

Transfiguration courtyard
114     It’s on the wall next to the door to the transfiguration classroom.
115     From the shortcut portrait, go right and into the courtyard,
       turn around, it’s left of the arch on the wall.
116     There is a lion statue near the shortcut portrait.
117     In the doorway of the tower in the middle of the courtyard is a crest.
118     There is a banner run in this courtyard.

Transfiguration classroom
119     As you enter turn around, it’s above the doors.

Astronomy tower
120     Coming from the training grounds, as you enter is on the left wall.
121     Down the corridor, go left to the circulair stairs.
       There is a statue here, it’s behind it.
122     Go up the stairs, halfway up go left down the stairs.
       Through the door, turn around, it’s above the door.
123     There is a lion statue in the corner.
124     Around the corner, straight ahead, up the steps, past the gate,
       it’s straight ahead behind a gate.
125     Turn around, it’s to the left of the gate on the wall.

So, this is all the locations of the crests. The other 25 are gained
by collecting mini crests. I hope it’s of use to you. Thank you for reading.