Nginx snippet for custom error pages that searches the root first and falls back to a default location.

custom_error_pages.conf

error_page 400 /400.html;
error_page 401 /401.html;
error_page 403 /403.html;
error_page 404 /404.html;
error_page 500 /500.html;
error_page 501 /501.html;
error_page 502 /502.html;
error_page 503 /503.html;
error_page 520 /520.html;
error_page 521 /521.html;
error_page 533 /533.html;

location ~* ^/(400|401|403|404|500|501|502|503|520|521|533)\.html$ {
	try_files $uri @error;
}

# default error pages
location @error {
	root /var/www/error;
}