CREATE TABLE table_204_880 (id DECIMAL, "year" DECIMAL, "competition" TEXT, "venue" TEXT, "position" TEXT, "event" TEXT, "notes" TEXT)

what venue appears most on the list ?
SELECT "venue" FROM table_204_880 GROUP BY "venue" ORDER BY COUNT(*) DESC LIMIT 1
SELECT "venue" FROM "table_204_880" GROUP BY "venue" ORDER BY COUNT(*) DESC NULLS LAST LIMIT 1