diff --git a/Subsurface-mobile.pro b/Subsurface-mobile.pro
index 3b79311e6..029f19356 100644
--- a/Subsurface-mobile.pro
+++ b/Subsurface-mobile.pro
@@ -97,6 +97,7 @@ SOURCES += subsurface-mobile-main.cpp \
 	core/taxonomy.cpp \
 	core/time.cpp \
 	core/trip.cpp \
+	core/triptable.cpp \
 	core/units.cpp \
 	core/uemis.cpp \
 	core/btdiscovery.cpp \
diff --git a/commands/command_divelist.cpp b/commands/command_divelist.cpp
index 923451e00..b38dcc14d 100644
--- a/commands/command_divelist.cpp
+++ b/commands/command_divelist.cpp
@@ -67,7 +67,7 @@ void DiveListBase::diveSiteCountChanged(struct dive_site *ds)
 dive *DiveListBase::addDive(DiveToAdd &d)
 {
 	if (d.trip)
-		add_dive_to_trip(d.dive.get(), d.trip);
+		d.trip->add_dive(d.dive.get());
 	if (d.site) {
 		d.site->add_dive(d.dive.get());
 		diveSiteCountChanged(d.site);
@@ -267,7 +267,7 @@ static std::unique_ptr<dive_trip> moveDiveToTrip(DiveToTrip &diveToTrip)
 	// Store old trip and get new trip we should associate this dive with
 	std::swap(trip, diveToTrip.trip);
 	if (trip)
-		add_dive_to_trip(diveToTrip.dive, trip);
+		trip->add_dive(diveToTrip.dive);
 	invalidate_dive_cache(diveToTrip.dive);		// Ensure that dive is written in git_save()
 	return res;
 }
diff --git a/core/CMakeLists.txt b/core/CMakeLists.txt
index 22237a79f..60343fe98 100644
--- a/core/CMakeLists.txt
+++ b/core/CMakeLists.txt
@@ -180,6 +180,7 @@ set(SUBSURFACE_CORE_LIB_SRCS
 	time.cpp
 	trip.cpp
 	trip.h
+	triptable.cpp
 	triptable.h
 	uemis-downloader.cpp
 	uemis.cpp
diff --git a/core/divelist.cpp b/core/divelist.cpp
index c60bddce0..b3ae8d10e 100644
--- a/core/divelist.cpp
+++ b/core/divelist.cpp
@@ -642,9 +642,9 @@ int comp_dives(const struct dive &a, const struct dive &b)
 			return -1;
 		if (!a.divetrip)
 			return 1;
-		if (trip_date(*a.divetrip) < trip_date(*b.divetrip))
+		if (a.divetrip->date() < b.divetrip->date())
 			return -1;
-		if (trip_date(*a.divetrip) > trip_date(*b.divetrip))
+		if (a.divetrip->date() > b.divetrip->date())
 			return 1;
 	}
 	if (a.number < b.number)
@@ -676,7 +676,7 @@ static void autogroup_dives(struct dive_table &table, struct trip_table &trip_ta
 
 	for (auto &entry: get_dives_to_autogroup(table)) {
 		for (auto it = table.begin() + entry.from; it != table.begin() + entry.to; ++it)
-			add_dive_to_trip(it->get(), entry.trip);
+			entry.trip->add_dive(it->get());
 		/* If this was newly allocated, add trip to list */
 		if (entry.created_trip)
 			trip_table.put(std::move(entry.created_trip));
@@ -911,7 +911,7 @@ void add_imported_dives(struct divelog &import_log, int flags)
 		struct dive_site *site = d->dive_site;
 		d->divetrip = NULL;
 		d->dive_site = NULL;
-		add_dive_to_trip(d.get(), trip);
+		trip->add_dive(d.get());
 		if (site)
 			site->add_dive(d.get());
 	}
diff --git a/core/load-git.cpp b/core/load-git.cpp
index e88a11694..b2d08af45 100644
--- a/core/load-git.cpp
+++ b/core/load-git.cpp
@@ -1401,7 +1401,7 @@ static void create_new_dive(timestamp_t when, struct git_parser_state *state)
 	state->active_dive->when = when;
 
 	if (state->active_trip)
-		add_dive_to_trip(state->active_dive.get(), state->active_trip.get());
+		state->active_trip->add_dive(state->active_dive.get());
 }
 
 static bool validate_date(int yyyy, int mm, int dd)
diff --git a/core/parse.cpp b/core/parse.cpp
index 5b2f83fe2..5aef2d0c9 100644
--- a/core/parse.cpp
+++ b/core/parse.cpp
@@ -261,7 +261,7 @@ void dive_end(struct parser_state *state)
 		return;
 	if (is_dive(state)) {
 		if (state->cur_trip)
-			add_dive_to_trip(state->cur_dive.get(), state->cur_trip.get());
+			state->cur_trip->add_dive(state->cur_dive.get());
 		// Note: we add dives in an unsorted way. The caller of the parsing
 		// function must sort dives.
 		fixup_dive(state->cur_dive.get());
diff --git a/core/save-git.cpp b/core/save-git.cpp
index ac0e24306..a8e1e6c8e 100644
--- a/core/save-git.cpp
+++ b/core/save-git.cpp
@@ -1004,7 +1004,7 @@ static int create_git_tree(git_repository *repo, struct dir *root, bool select_o
 		}
 
 		/* Create the date-based hierarchy */
-		utc_mkdate(trip ? trip_date(*trip) : dive->when, &tm);
+		utc_mkdate(trip ? trip->date() : dive->when, &tm);
 		tree = mktree(repo, root, "%04d", tm.tm_year);
 		tree = mktree(repo, tree, "%02d", tm.tm_mon + 1);
 
diff --git a/core/save-xml.cpp b/core/save-xml.cpp
index 85ed6cc21..40b64850a 100644
--- a/core/save-xml.cpp
+++ b/core/save-xml.cpp
@@ -545,7 +545,7 @@ int save_dive(FILE *f, const struct dive &dive, bool anonymize)
 static void save_trip(struct membuffer *b, dive_trip &trip, bool anonymize)
 {
 	put_format(b, "<trip");
-	show_date(b, trip_date(trip));
+	show_date(b, trip.date());
 	show_utf8(b, trip.location.c_str(), " location=\'", "\'", 1);
 	put_format(b, ">\n");
 	show_utf8(b, trip.notes.c_str(), "<notes>", "</notes>\n", 0);
diff --git a/core/string-format.cpp b/core/string-format.cpp
index 71d21f8e2..95050c260 100644
--- a/core/string-format.cpp
+++ b/core/string-format.cpp
@@ -301,8 +301,8 @@ QString formatMinutes(int seconds)
 
 QString formatTripTitle(const dive_trip &trip)
 {
-	timestamp_t when = trip_date(trip);
-	bool getday = trip_is_single_day(trip);
+	timestamp_t when = trip.date();
+	bool getday = trip.is_single_day();
 
 	QDateTime localTime = timestampToDateTime(when);
 
diff --git a/core/trip.cpp b/core/trip.cpp
index 311fc5b78..1869dbd75 100644
--- a/core/trip.cpp
+++ b/core/trip.cpp
@@ -9,38 +9,17 @@
 #include "subsurface-string.h"
 #include "selection.h"
 
-#ifdef DEBUG_TRIP
-void dump_trip_list()
-{
-	timestamp_t last_time = 0;
-
-	for (auto &trip: divelog.trips) {
-		struct tm tm;
-		utc_mkdate(trip_date(*trip), &tm);
-		if (trip_date(*trip) < last_time)
-			printf("\n\ntrip_table OUT OF ORDER!!!\n\n\n");
-		printf("%s trip %d to \"%s\" on %04u-%02u-%02u %02u:%02u:%02u (%d dives - %p)\n",
-		       trip->autogen ? "autogen " : "",
-		       i + 1, trip->location.c_str(),
-		       tm.tm_year, tm.tm_mon + 1, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec,
-		       static_cast<int>(trip->dives.size()), trip.get());
-		last_time = trip_date(*trip);
-	}
-	printf("-----\n");
-}
-#endif
-
 dive_trip::dive_trip() : id(dive_getUniqID())
 {
 }
 
 dive_trip::~dive_trip() = default;
 
-timestamp_t trip_date(const struct dive_trip &trip)
+timestamp_t dive_trip::date() const
 {
-	if (trip.dives.empty())
+	if (dives.empty())
 		return 0;
-	return trip.dives[0]->when;
+	return dives[0]->when;
 }
 
 static timestamp_t trip_enddate(const struct dive_trip &trip)
@@ -52,14 +31,14 @@ static timestamp_t trip_enddate(const struct dive_trip &trip)
 
 /* Add dive to a trip. Caller is responsible for removing dive
  * from trip beforehand. */
-void add_dive_to_trip(struct dive *dive, dive_trip *trip)
+void dive_trip::add_dive(struct dive *dive)
 {
-	if (dive->divetrip == trip)
+	if (dive->divetrip == this)
 		return;
 	if (dive->divetrip)
 		report_info("Warning: adding dive to trip, which already has a trip set");
-	range_insert_sorted(trip->dives, dive, comp_dives_ptr);
-	dive->divetrip = trip;
+	range_insert_sorted(dives, dive, comp_dives_ptr);
+	dive->divetrip = this;
 }
 
 /* remove a dive from the trip it's associated to, but don't delete the
@@ -115,13 +94,6 @@ std::pair<dive_trip *, std::unique_ptr<dive_trip>> get_trip_for_new_dive(const s
 	return { t, std::move(trip) };
 }
 
-/* lookup of trip in main trip_table based on its id */
-dive_trip *trip_table::get_by_uniq_id(int tripId) const
-{
-	auto it = std::find_if(begin(), end(), [tripId](auto &t) { return t->id == tripId; });
-	return it != end() ? it->get() : nullptr;
-}
-
 /* Check if two trips overlap time-wise up to trip threshold. */
 bool trips_overlap(const struct dive_trip &t1, const struct dive_trip &t2)
 {
@@ -129,10 +101,10 @@ bool trips_overlap(const struct dive_trip &t1, const struct dive_trip &t2)
 	if (t1.dives.empty() || t2.dives.empty())
 		return 0;
 
-	if (trip_date(t1) < trip_date(t2))
-		return trip_enddate(t1) + TRIP_THRESHOLD >= trip_date(t2);
+	if (t1.date() < t2.date())
+		return trip_enddate(t1) + TRIP_THRESHOLD >= t2.date();
 	else
-		return trip_enddate(t2) + TRIP_THRESHOLD >= trip_date(t1);
+		return trip_enddate(t2) + TRIP_THRESHOLD >= t1.date();
 }
 
 /*
@@ -250,17 +222,16 @@ static bool is_same_day(timestamp_t trip_when, timestamp_t dive_when)
 	return (tmd.tm_mday == tmt.tm_mday) && (tmd.tm_mon == tmt.tm_mon) && (tmd.tm_year == tmt.tm_year);
 }
 
-bool trip_is_single_day(const struct dive_trip &trip)
+bool dive_trip::is_single_day() const
 {
-	if (trip.dives.size() <= 1)
+	if (dives.size() <= 1)
 		return true;
-	return is_same_day(trip.dives.front()->when,
-			   trip.dives.back()->when);
+	return is_same_day(dives.front()->when, dives.back()->when);
 }
 
-int trip_shown_dives(const struct dive_trip *trip)
+int dive_trip::shown_dives() const
 {
-	return std::count_if(trip->dives.begin(), trip->dives.end(),
+	return std::count_if(dives.begin(), dives.end(),
 			     [](const dive *d) { return !d->hidden_by_filter; });
 }
 
diff --git a/core/trip.h b/core/trip.h
index 1ada441bd..2aa5f274b 100644
--- a/core/trip.h
+++ b/core/trip.h
@@ -17,21 +17,21 @@ struct dive_trip
 	bool autogen = false;
 	bool selected = false;
 
-	void sort_dives();
-
 	dive_trip();
 	~dive_trip();
+
+	void sort_dives();
+	void add_dive(struct dive *);
+	timestamp_t date() const;
+	bool is_single_day() const;
+	int shown_dives() const;
 };
 
 int comp_trips(const dive_trip &t1, const dive_trip &t2);
 
-extern void add_dive_to_trip(struct dive *, dive_trip *);
 extern struct dive_trip *unregister_dive_from_trip(struct dive *dive);
 
-extern timestamp_t trip_date(const struct dive_trip &trip);
-
 extern std::unique_ptr<dive_trip> create_trip_from_dive(const struct dive *dive);
-extern dive_trip *create_and_hookup_trip_from_dive(const struct dive *dive, struct trip_table &trip_table_arg);
 
 // Result item of get_dives_to_autogroup()
 struct dives_to_autogroup_result {
@@ -46,12 +46,6 @@ extern std::pair<dive_trip *, std::unique_ptr<dive_trip>> get_trip_for_new_dive(
 extern bool trips_overlap(const struct dive_trip &t1, const struct dive_trip &t2);
 
 extern std::unique_ptr<dive_trip> combine_trips(struct dive_trip *trip_a, struct dive_trip *trip_b);
-extern bool trip_is_single_day(const struct dive_trip &trip);
-extern int trip_shown_dives(const struct dive_trip *trip);
-
-#ifdef DEBUG_TRIP
-extern void dump_trip_list();
-#endif
 
 /* Make pointers to dive_trip "Qt metatypes" so that they can be
  * passed through QVariants and through QML. See comment in dive.h. */
diff --git a/core/triptable.cpp b/core/triptable.cpp
new file mode 100644
index 000000000..841a6b609
--- /dev/null
+++ b/core/triptable.cpp
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "triptable.h"
+#include "trip.h"
+
+#ifdef DEBUG_TRIP
+void dump_trip_list()
+{
+	timestamp_t last_time = 0;
+
+	for (auto &trip: divelog.trips) {
+		struct tm tm;
+		utc_mkdate(trip->date(), &tm);
+		if (trip->date() < last_time)
+			printf("\n\ntrip_table OUT OF ORDER!!!\n\n\n");
+		printf("%s trip %d to \"%s\" on %04u-%02u-%02u %02u:%02u:%02u (%d dives - %p)\n",
+		       trip->autogen ? "autogen " : "",
+		       i + 1, trip->location.c_str(),
+		       tm.tm_year, tm.tm_mon + 1, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec,
+		       static_cast<int>(trip->dives.size()), trip.get());
+		last_time = trip->date();
+	}
+	printf("-----\n");
+}
+#endif
+
+/* lookup of trip in main trip_table based on its id */
+dive_trip *trip_table::get_by_uniq_id(int tripId) const
+{
+	auto it = std::find_if(begin(), end(), [tripId](auto &t) { return t->id == tripId; });
+	return it != end() ? it->get() : nullptr;
+}
diff --git a/core/triptable.h b/core/triptable.h
index 1b4facc0c..73cba9652 100644
--- a/core/triptable.h
+++ b/core/triptable.h
@@ -12,6 +12,10 @@ struct trip_table : public sorted_owning_table<dive_trip, &comp_trips> {
 	dive_trip *get_by_uniq_id(int tripId) const;
 };
 
+#ifdef DEBUG_TRIP
+extern void dump_trip_list();
+#endif
+
 /* Make pointers to trip_table "Qt metatypes" so that they can be
  * passed through QVariants and through QML. See comment in dive.h. */
 #include <QObject>
diff --git a/desktop-widgets/tab-widgets/TabDiveNotes.cpp b/desktop-widgets/tab-widgets/TabDiveNotes.cpp
index b0a50e83c..439659a84 100644
--- a/desktop-widgets/tab-widgets/TabDiveNotes.cpp
+++ b/desktop-widgets/tab-widgets/TabDiveNotes.cpp
@@ -169,7 +169,7 @@ void TabDiveNotes::updateDateTime(const struct dive *d)
 
 void TabDiveNotes::updateTripDate(const struct dive_trip *t)
 {
-	QDateTime localTime = timestampToDateTime(trip_date(*t));
+	QDateTime localTime = timestampToDateTime(t->date());
 	ui.dateEdit->setDate(localTime.date());
 }
 
diff --git a/qt-models/divetripmodel.cpp b/qt-models/divetripmodel.cpp
index c65d090b3..baf7d2937 100644
--- a/qt-models/divetripmodel.cpp
+++ b/qt-models/divetripmodel.cpp
@@ -69,7 +69,7 @@ QString DiveTripModelBase::tripShortDate(const dive_trip *trip)
 {
 	if (!trip)
 		return QString();
-	QDateTime firstTime = timestampToDateTime(trip_date(*trip));
+	QDateTime firstTime = timestampToDateTime(trip->date());
 	QString firstMonth = firstTime.toString("MMM");
 	return QStringLiteral("%1\n'%2").arg(firstMonth,firstTime.toString("yy"));
 }
@@ -79,13 +79,13 @@ QString DiveTripModelBase::tripTitle(const dive_trip *trip)
 	if (!trip)
 		return QString();
 	QString numDives = tr("(%n dive(s))", "", static_cast<int>(trip->dives.size()));
-	int shown = trip_shown_dives(trip);
+	int shown = trip->shown_dives();
 	QString shownDives = shown != !trip->dives.empty() ? QStringLiteral(" ") + tr("(%L1 shown)").arg(shown) : QString();
 	QString title = QString::fromStdString(trip->location);
 
 	if (title.isEmpty()) {
 		// so use the date range
-		QDateTime firstTime = timestampToDateTime(trip_date(*trip));
+		QDateTime firstTime = timestampToDateTime(trip->date());
 		QString firstMonth = firstTime.toString("MMM");
 		QString firstYear = firstTime.toString("yyyy");
 		QDateTime lastTime = timestampToDateTime(trip->dives[0]->when);
@@ -125,7 +125,7 @@ QVariant DiveTripModelBase::tripData(const dive_trip *trip, int column, int role
 		switch (column) {
 		case DiveTripModelBase::NR:
 			QString shownText;
-			int countShown = trip_shown_dives(trip);
+			int countShown = trip->shown_dives();
 			if (countShown < static_cast<int>(trip->dives.size()))
 				shownText = tr("(%1 shown)").arg(countShown);
 			return formatTripTitleWithDives(*trip) + " " + shownText;
@@ -814,7 +814,7 @@ dive *DiveTripModelTree::Item::getDive() const
 
 timestamp_t DiveTripModelTree::Item::when() const
 {
-	return d_or_t.trip ? trip_date(*d_or_t.trip) : d_or_t.dive->when;
+	return d_or_t.trip ? d_or_t.trip->date() : d_or_t.dive->when;
 }
 
 dive_or_trip DiveTripModelTree::tripOrDive(const QModelIndex &index) const
diff --git a/stats/statsvariables.cpp b/stats/statsvariables.cpp
index e0fa377ea..8f31190bc 100644
--- a/stats/statsvariables.cpp
+++ b/stats/statsvariables.cpp
@@ -75,7 +75,7 @@ struct TripWrapper {
 	timestamp_t date;
 	TripWrapper(const dive_trip *t) : t(t),
 		name(t ? formatTripTitle(*t) : QString()),
-		date(t ? trip_date(*t) : 0)
+		date(t ? t->date() : 0)
 	{
 	}
 	bool operator<(const TripWrapper &t2) const {