diff --git a/src/reports.c b/src/reports.c
index 552b99dff..3ddc0a7ac 100644
--- a/src/reports.c
+++ b/src/reports.c
@@ -1371,6 +1371,9 @@ static void cb_add_seen(region *r, unit *u, void *cbdata) {
     unused_arg(cbdata);
     if (u->faction) {
         add_seen(u->faction->seen, r, see_travel, false);
+#ifdef SMART_INTERVALS
+        update_interval(u->faction, r);
+#endif
     }
 }
 
@@ -1403,7 +1406,7 @@ static void prepare_reports(void)
         }
 
         /* Region owner get always the Lighthouse report */
-        if (check_param(global.parameters, "rules.region_owner_pay_building", bt_lighthouse->_name)) {
+        if (bt_lighthouse && check_param(global.parameters, "rules.region_owner_pay_building", bt_lighthouse->_name)) {
             for (b = rbuildings(r); b; b = b->next) {
                 if (b && b->type == bt_lighthouse) {
                     u = building_owner(b);
@@ -1510,37 +1513,45 @@ static region *firstregion(faction * f)
 #endif
 }
 
-static void prepare_report(struct report_context *ctx, faction *f)
+static void view_region(region *r, faction *f) {
+    plane *p = rplane(r);
+    void(*view) (struct seen_region **, region *, faction *) = view_default;
+
+    if (p && fval(p, PFL_SEESPECIAL)) {
+        /* TODO: this is not very customizable */
+        view = (strcmp(p->name, "Regatta") == 0) ? view_regatta : view_neighbours;
+    }
+    view(f->seen, r, f);
+}
+
+void prepare_seen(faction *f)
 {
     region *r;
     struct seen_region *sr;
 
-    ctx->f = f;
-    ctx->report_time = time(NULL);
-    ctx->first = firstregion(f);
-    ctx->last = lastregion(f);
-    ctx->addresses = NULL;
-    ctx->userdata = NULL;
-
-    for (r = ctx->first, sr = NULL; sr == NULL && r != ctx->last; r = r->next) {
+    for (r = f->first, sr = NULL; sr == NULL && r != f->last; r = r->next) {
         sr = find_seen(f->seen, r);
     }
 
     for (; sr != NULL; sr = sr->next) {
         if (sr->mode > see_neighbour) {
             region *r = sr->r;
-            plane *p = rplane(r);
-            void(*view) (struct seen_region **, region *, faction *) = view_default;
-
-            if (p && fval(p, PFL_SEESPECIAL)) {
-                /* TODO: this is not very customizable */
-                view = (strcmp(p->name, "Regatta") == 0) ? view_regatta : view_neighbours;
-            }
-            view(f->seen, r, f);
+            view_region(r, f);
         }
     }
-    get_seen_interval(ctx->f->seen, &ctx->first, &ctx->last);
-    link_seen(ctx->f->seen, ctx->first, ctx->last);
+    get_seen_interval(f->seen, &f->first, &f->last);
+    link_seen(f->seen, f->first, f->last);
+}
+
+static void prepare_report(struct report_context *ctx, faction *f)
+{
+    prepare_seen(f);
+    ctx->f = f;
+    ctx->report_time = time(NULL);
+    ctx->addresses = NULL;
+    ctx->userdata = NULL;
+    ctx->first = firstregion(f);
+    ctx->last = lastregion(f);
 }
 
 int write_reports(faction * f, time_t ltime)
diff --git a/src/reports.h b/src/reports.h
index e5439812d..2b3f9d51d 100644
--- a/src/reports.h
+++ b/src/reports.h
@@ -56,6 +56,7 @@ extern "C" {
     void spunit(struct strlist **SP, const struct faction *f,
         const struct unit *u, unsigned int indent, int mode);
 
+    void prepare_seen(struct faction *f);
     int reports(void);
     int write_reports(struct faction *f, time_t ltime);
     int init_reports(void);
diff --git a/src/seen.c b/src/seen.c
index e0786dce2..2bbc529b0 100644
--- a/src/seen.c
+++ b/src/seen.c
@@ -122,7 +122,7 @@ void get_seen_interval(struct seen_region *seen[], struct region **firstp, struc
     *lastp = last;
 }
 
-bool add_seen(struct seen_region *seehash[], struct region *r, int mode, bool dis)
+bool add_seen(struct seen_region *seehash[], struct region *r, unsigned char mode, bool dis)
 {
     seen_region *find = find_seen(seehash, r);
     if (find == NULL) {
diff --git a/src/seen.h b/src/seen.h
index c46a8a7e0..9e6312d78 100644
--- a/src/seen.h
+++ b/src/seen.h
@@ -51,7 +51,7 @@ void free_seen(void);
 void link_seen(struct seen_region *seehash[], const struct region * first, const struct region * last);
 struct seen_region *find_seen(struct seen_region *seehash[], const struct region * r);
 void get_seen_interval(struct seen_region *seen[], struct region **firstp, struct region **lastp);
-bool add_seen(struct seen_region *seehash[], struct region *r, int mode, bool dis);
+bool add_seen(struct seen_region *seehash[], struct region *r, unsigned char mode, bool dis);
 void link_seen(struct seen_region *seehash[], const struct region *first, const struct region *last);
 #ifdef __cplusplus
 }
diff --git a/src/seen.test.c b/src/seen.test.c
index 6a4678c5e..be2189c14 100644
--- a/src/seen.test.c
+++ b/src/seen.test.c
@@ -2,24 +2,83 @@
 #include <config.h>
 #include "seen.h"
 #include "reports.h"
+#include "travelthru.h"
 
 #include <kernel/region.h>
+#include <kernel/unit.h>
+#include <kernel/faction.h>
 
 #include <CuTest.h>
 #include <tests.h>
 
+static void setup_seen(int x, int y) {
+    int dir;
+
+    for (dir = 0; dir != MAXDIRECTIONS; ++dir) {
+        test_create_region(x+delta_x[dir], y+delta_y[dir], 0);
+    }
+}
+
+static void test_prepare_seen(CuTest *tc) {
+    region *r;
+    faction *f;
+    unit *u;
+
+    test_cleanup();
+    f = test_create_faction(0);
+    r = test_create_region(0, 0, 0);
+    u = test_create_unit(f, r);
+    f->seen = seen_init();
+    add_seen(f->seen, r, see_unit, false);
+    setup_seen(0, 0);
+    r = test_create_region(2, 2, 0);
+    setup_seen(2, 2);
+    travelthru_add(r, u);
+
+    init_reports();
+    prepare_seen(f);
+    CuAssertPtrEquals(tc, regions, f->first);
+    CuAssertPtrEquals(tc, 0, f->last);
+    seen_done(f->seen);
+    test_cleanup();
+}
+
+static void test_seen_travelthru(CuTest *tc) {
+    seen_region *sr;
+    region *r;
+    faction *f;
+    unit *u;
+
+    test_cleanup();
+    setup_seen(0, 0);
+    r = test_create_region(0, 0, 0);
+    f = test_create_faction(0);
+    u = test_create_unit(f, 0);
+    travelthru_add(r, u);
+    init_reports();
+    view_default(f->seen, r, f);
+    get_seen_interval(f->seen, &f->first, &f->last);
+    link_seen(f->seen, f->first, f->last);
+    CuAssertPtrEquals(tc, regions, f->first);
+    CuAssertPtrEquals(tc, 0, f->last);
+    sr = find_seen(f->seen, regions);
+    CuAssertPtrEquals(tc, regions, sr->r);
+    CuAssertIntEquals(tc, see_neighbour, sr->mode);
+    sr = find_seen(f->seen, r);
+    CuAssertPtrEquals(tc, r, sr->r);
+    CuAssertIntEquals(tc, see_travel, sr->mode);
+    test_cleanup();
+}
+
 static void test_seen_region(CuTest *tc) {
     seen_region **seen, *sr;
     region *r;
-    int dir;
 
     test_cleanup();
-    for (dir=0;dir!=MAXDIRECTIONS;++dir) {
-        region *rn = test_create_region(delta_x[dir], delta_y[dir], 0);
-    }
+    setup_seen(0, 0);
     r = test_create_region(0, 0, 0);
     seen = seen_init();
-    add_seen(seen, r, see_unit, true);
+    add_seen(seen, r, see_unit, false);
     sr = find_seen(seen,  r);
     CuAssertPtrEquals(tc, r, sr->r);
     seen_done(seen);
@@ -28,16 +87,13 @@ static void test_seen_region(CuTest *tc) {
 
 static void test_seen_interval_backward(CuTest *tc) {
     region *r, *first, *last;
-    seen_region **seen, *sr;
-    int dir;
+    seen_region **seen;
 
     test_cleanup();
     r = test_create_region(0, 0, 0);
-    for (dir=0;dir!=MAXDIRECTIONS;++dir) {
-        region *rn = test_create_region(delta_x[dir], delta_y[dir], 0);
-    }
+    setup_seen(0, 0);
     seen = seen_init();
-    add_seen(seen, r, see_unit, true);
+    add_seen(seen, r, see_unit, false);
     view_default(seen, r, 0);
     first = r;
     last = 0;
@@ -49,13 +105,10 @@ static void test_seen_interval_backward(CuTest *tc) {
 
 static void test_seen_interval_forward(CuTest *tc) {
     region *r, *first, *last;
-    seen_region **seen, *sr;
-    int dir;
+    seen_region **seen;
 
     test_cleanup();
-    for (dir=0;dir!=MAXDIRECTIONS;++dir) {
-        region *rn = test_create_region(delta_x[dir], delta_y[dir], 0);
-    }
+    setup_seen(0, 0);
     r = test_create_region(0, 0, 0);
     seen = seen_init();
     add_seen(seen, r, see_unit, true);
@@ -71,6 +124,8 @@ static void test_seen_interval_forward(CuTest *tc) {
 CuSuite *get_seen_suite(void)
 {
     CuSuite *suite = CuSuiteNew();
+    SUITE_ADD_TEST(suite, test_prepare_seen);
+    SUITE_ADD_TEST(suite, test_seen_travelthru);
     SUITE_ADD_TEST(suite, test_seen_region);
     SUITE_ADD_TEST(suite, test_seen_interval_backward);
     SUITE_ADD_TEST(suite, test_seen_interval_forward);