diff --git a/api/src/errors/http-error.ts b/api/src/errors/http-error.ts
index ed9eea3..17d20be 100644
--- a/api/src/errors/http-error.ts
+++ b/api/src/errors/http-error.ts
@@ -28,7 +28,7 @@ export class InvalidParameter extends HTTPException{
         super(400, { message:
             paramName
             ? `Provided parameter '${paramName}' is invalid.`
-            : 'Provided invalid parameter.'
+            : 'Provided invalid request parameter(s) or some required parameter is missing.'
         })
     }
 }
diff --git a/api/src/routes/logbook.ts b/api/src/routes/logbook.ts
index fa36f1e..d13ceba 100644
--- a/api/src/routes/logbook.ts
+++ b/api/src/routes/logbook.ts
@@ -1,13 +1,151 @@
 import { Hono } from 'hono'
+import { DatabaseError } from '../errors'
+import { getDbContext } from '../db/client'
+import { logbook } from '../db/schema'
+import { and, eq } from 'drizzle-orm'
+import { getUser } from '../lib/user-auth'
+import { Message } from '../types/response'
+
+import * as z from 'zod'
+import httpZValidator from '../lib/http-z-validator'
 
 const app = new Hono()
 
-app.get('/list', (c) => {
-  return c.json(
-    {
-      message: 'List all logbook entries'
-    }
-  )
+/**
+ * Lists all logbook entries of the logged in user
+ */
+app.get('/list', async (c) => {
+  const db = getDbContext(c);
+  const user = await getUser(c);
+
+  try{
+    const logbookEntries = await db.select({
+      entryId: logbook.id,
+      attractionId: logbook.attractionId,
+      timestamp: logbook.timestamp,
+      expectedWaittime: logbook.expectedWaittime,
+      realWaittime: logbook.realWaittime
+    }).from(logbook)
+    .where(eq(logbook.userId, user.id));
+
+    return c.json(logbookEntries);
+  }
+  catch{
+    throw new DatabaseError();
+  }
+})
+
+/**
+ * Adds new entry to the logbook of the current user
+ */
+app.post('/add-entry', httpZValidator('query', z.strictObject({
+  attractionId: z.coerce.number(),
+  timestamp: z.coerce.number().min(0).positive(),
+  expectedWaittime: z.coerce.number().optional(),
+  realWaittime: z.coerce.number().optional()
+})),
+async (c) => {
+  const db = getDbContext(c);
+  const user = await getUser(c);
+
+  const params = c.req.valid('query');
+
+  try{
+    const res = await db.insert(logbook).values({
+      userId: user.id,
+      attractionId: params.attractionId,
+      timestamp: params.timestamp,
+      expectedWaittime: params.expectedWaittime,
+      realWaittime: params.realWaittime
+    }).onConflictDoNothing().returning();
+
+    const newEntry = res[0];
+
+    const message = res.length > 0
+    ? 'Added new entry to logbook.'
+    : 'Entry already exists. No changes made.';
+
+    return c.json(new Message(message, {
+      entryId: newEntry.id,
+      attractionId: newEntry.attractionId,
+      timestamp: newEntry.timestamp,
+      expectedWaittime: newEntry.expectedWaittime,
+      realWaittime: newEntry.realWaittime
+    }));
+  }
+  catch{
+    throw new DatabaseError();
+  }
+})
+
+/**
+ * Updates waittime information of specified entry (by entryId)
+ */
+app.put('update-entry', httpZValidator('query', z.strictObject({
+  entryId: z.coerce.number(),
+  expectedWaittime: z.coerce.number().optional(),
+  realWaittime: z.coerce.number().optional()
+}).refine((data) => data.expectedWaittime || data.realWaittime)),
+async (c) => {
+  const db = getDbContext(c);
+  const user = await getUser(c);
+  const params = c.req.valid('query');
+
+  try{
+    const res = await db.update(logbook).set({
+      expectedWaittime: params.expectedWaittime,
+      realWaittime: params.realWaittime
+    }).where(and(
+      eq(logbook.userId, user.id),
+      eq(logbook.id, params.entryId)
+    )).returning();
+
+    const modifiedEntry = res[0];
+
+    return c.json(res.length > 0
+      ? new Message('Updated logbook entry.', {
+      entryId: modifiedEntry.id,
+      attractionId: modifiedEntry.attractionId,
+      timestamp: modifiedEntry.timestamp,
+      expectedWaittime: modifiedEntry.expectedWaittime,
+      realWaittime: modifiedEntry.realWaittime
+    })
+    : new Message('Requested entry does not exist. No changes made.')
+    );
+  }
+  catch{
+    throw new DatabaseError();
+  }
+})
+
+/**
+ * Removes specified logbook entry by entryId
+ */
+app.delete('remove-entry', httpZValidator('query', z.strictObject({
+  entryId: z.coerce.number()
+})),
+async (c) => {
+  const db = getDbContext(c);
+  const user = await getUser(c);
+  const params = c.req.valid('query');
+
+  try{
+    const res = await db.delete(logbook).where(
+      and(
+        eq(logbook.userId, user.id),
+        eq(logbook.id, params.entryId)
+      )
+    ).returning();
+
+    const message = res.length > 0
+    ? `Logbook entry with id ${params.entryId} was removed.`
+    : `No logbook entry with id ${params.entryId} found. No changes made.`;
+
+    return c.json(new Message(message));
+  }
+  catch{
+    throw new DatabaseError();
+  }
 })
 
 export default app
\ No newline at end of file