diff --git a/src/reports.c b/src/reports.c
index 11d913ef5..c38fdeae0 100644
--- a/src/reports.c
+++ b/src/reports.c
@@ -1135,19 +1135,24 @@ static void add_seen(region *r, seen_mode mode) {
     }
 }
 
-static void faction_add_seen(faction *f, region *r, seen_mode mode) {
+static void add_seen_nb(faction *f, region *r, seen_mode mode) {
+    region *first = r, *last = r;
     add_seen(r, mode);
     if (mode > seen_neighbour) {
         region *next[MAXDIRECTIONS];
         int d;
         get_neighbours(r, next);
         for (d = 0; d != MAXDIRECTIONS; ++d) {
-            if (next[d] && next[d]->seen.mode<seen_neighbour) {
-                faction_add_seen(f, next[d], seen_neighbour);
+            region *rn = next[d];
+            if (rn && rn->seen.mode<seen_neighbour) {
+                add_seen(rn, seen_neighbour);
+                if (first->index>rn->index) first = rn;
+                if (last->index<rn->index) last = rn;
             }
         }
     }
-    update_interval(f, r);
+    update_interval(f, first);
+    update_interval(f, last);
 }
 
 /** mark all regions seen by the lighthouse.
@@ -1162,7 +1167,7 @@ static void prepare_lighthouse(building * b, report_context *ctx)
     for (ql = rlist, qi = 0; ql; ql_advance(&ql, &qi, 1)) {
         region *rl = (region *)ql_get(ql, qi);
         if (!fval(rl->terrain, FORBIDDEN_REGION)) {
-            faction_add_seen(f, rl, seen_lighthouse);
+            add_seen_nb(f, rl, seen_lighthouse);
         }
     }
     ql_free(rlist);
@@ -1286,7 +1291,7 @@ static region *firstregion(faction * f)
 static void cb_add_seen(region *r, unit *u, void *cbdata) {
     faction *f = (faction *)cbdata;
     if (u->faction==f) {
-        faction_add_seen(f, r, seen_travel);
+        add_seen_nb(f, r, seen_travel);
     }
 }
 
@@ -1327,7 +1332,7 @@ void prepare_report(report_context *ctx, faction *f)
                         if (u && u->faction==f) {
                             prepare_lighthouse(b, ctx);
                             if (u_race(u) != get_race(RC_SPELL) || u->number == RS_FARVISION) {
-                                faction_add_seen(f, r, seen_unit);
+                                add_seen_nb(f, r, seen_unit);
                             }
                         }
                     }
@@ -1338,7 +1343,7 @@ void prepare_report(report_context *ctx, faction *f)
         for (u = r->units; u; u = u->next) {
             if (u->faction==f) {
                 if (u_race(u) != get_race(RC_SPELL) || u->number == RS_FARVISION) {
-                    faction_add_seen(f, r, seen_unit);
+                    add_seen_nb(f, r, seen_unit);
                 }
                 if (fval(r, RF_LIGHTHOUSE)) {
                     if (u->building && u->building->type == bt_lighthouse && inside_building(u)) {
@@ -1349,7 +1354,7 @@ void prepare_report(report_context *ctx, faction *f)
             }
         }
 
-        if (fval(r, RF_TRAVELUNIT)) {
+        if (fval(r, RF_TRAVELUNIT) && r->seen.mode<seen_travel) {
             travelthru_map(r, cb_add_seen, f);
         }
     }
diff --git a/src/reports.test.c b/src/reports.test.c
index 1cf5b023b..d9b427ff2 100644
--- a/src/reports.test.c
+++ b/src/reports.test.c
@@ -410,7 +410,11 @@ static void test_seen_travelthru(CuTest *tc) {
     r3 = test_create_region(2, 0, 0);
 
     u = test_create_unit(f, r1);
+    CuAssertPtrEquals(tc, r1, f->first);
+    CuAssertPtrEquals(tc, r1, f->last);
     travelthru_add(r2, u);
+    CuAssertPtrEquals(tc, r1, f->first);
+    CuAssertPtrEquals(tc, r3, f->last);
     prepare_report(&ctx, f);
     CuAssertPtrEquals(tc, r1, ctx.first);
     CuAssertPtrEquals(tc, 0, ctx.last);
diff --git a/src/travelthru.c b/src/travelthru.c
index 8e1fc946b..e55cacaa0 100644
--- a/src/travelthru.c
+++ b/src/travelthru.c
@@ -64,6 +64,8 @@ attrib_type at_travelunit = {
 */
 void travelthru_add(region * r, unit * u)
 {
+    region *next[MAXDIRECTIONS];
+    int d;
     attrib *a;
     quicklist *ql;
 
@@ -84,6 +86,10 @@ void travelthru_add(region * r, unit * u)
     * could be in regions that are located before the [first, last] interval,
     * and recalculation is needed */
     update_interval(u->faction, r);
+    get_neighbours(r, next);
+    for (d=0;d!=MAXDIRECTIONS;++d) {
+        update_interval(u->faction, next[d]);
+    }
 }
 
 bool travelthru_cansee(const struct region *r, const struct faction *f, const struct unit *u) {